tests: recognize a nonstart #alt as a #!alt

[nit.git] / c_src / compiling___compiling_icode._sep.c
diff --git a/c_src/compiling___compiling_icode._sep.c b/c_src/compiling___compiling_icode._sep.c

index ba05da8..b9d8cd0 100644 (file)
--- a/c_src/compiling___compiling_icode._sep.c
+++ b/c_src/compiling___compiling_icode._sep.c
@@ -18,10 +18,11 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
              static val_t once_value_12; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 31;
+  fra.me.line = 32;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___register;
    fra.me.has_broke = 0;
    fra.me.REG_size = 8;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -32,7 +33,7 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
    fra.me.REG[7] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:34 */
+  /* compiling/compiling_icode.nit:35 */
    fra.me.REG[2] = CALL_icode___icode_base___IRegister___stype(fra.me.REG[1])(fra.me.REG[1]);
    REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[2], COLOR_metamodel___static_type___MMTypeNone, ID_metamodel___static_type___MMTypeNone)) /*cast MMTypeNone*/;
    if (UNTAG_Bool(REGB0)) {
@@ -46,14 +47,14 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
      fra.me.REG[2] = fra.me.REG[2];
      goto label2;
    }
-  /* ./compiling//compiling_icode.nit:35 */
+  /* compiling/compiling_icode.nit:36 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 35);
+    nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 36);
    }
    fra.me.REG[3] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:36 */
+  /* compiling/compiling_icode.nit:37 */
    REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___closure(fra.me.REG[0])(fra.me.REG[0]);
    if (UNTAG_Bool(REGB0)) {
      REGB0 = CALL_analysis___allocate_iregister_slots___IRegister___is_local(fra.me.REG[1])(fra.me.REG[1]);
@@ -66,22 +67,22 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
      REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids2(fra.me.REG[0])!=NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
      } else {
-      nit_abort("Uninitialized attribute %s", "_ids2", LOCATE_compiling___compiling_icode, 36);
+      nit_abort("Uninitialized attribute %s", "_ids2", LOCATE_compiling___compiling_icode, 37);
      }
      fra.me.REG[4] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids2(fra.me.REG[0]);
      fra.me.REG[3] = fra.me.REG[4];
    }
-  /* ./compiling//compiling_icode.nit:37 */
+  /* compiling/compiling_icode.nit:38 */
    REGB0 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:38 */
+    /* compiling/compiling_icode.nit:39 */
      fra.me.REG[4] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
      fra.me.REG[2] = fra.me.REG[4];
      goto label2;
    } else {
-    /* ./compiling//compiling_icode.nit:40 */
+    /* compiling/compiling_icode.nit:41 */
      fra.me.REG[4] = CALL_analysis___allocate_iregister_slots___IRegister___slot_index(fra.me.REG[1])(fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:41 */
+    /* compiling/compiling_icode.nit:42 */
      REGB0 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
      } else {
@@ -90,14 +91,14 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
          REGB1 = TAG_Bool(false);
          REGB0 = REGB1;
        } else {
-        /* ./../lib/standard//kernel.nit:210 */
+        /* ../lib/standard/kernel.nit:227 */
          REGB1 = TAG_Bool((fra.me.REG[4])==(NIT_NULL));
-        /* ./compiling//compiling_icode.nit:41 */
+        /* compiling/compiling_icode.nit:42 */
          REGB0 = REGB1;
        }
      }
      if (UNTAG_Bool(REGB0)) {
-      /* ./compiling//compiling_icode.nit:43 */
+      /* compiling/compiling_icode.nit:44 */
        if (!once_value_3) {
          fra.me.REG[5] = BOX_NativeString("NIT_NULL");
          REGB0 = TAG_Int(8);
@@ -106,23 +107,23 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
          register_static_object(&once_value_3);
        } else fra.me.REG[5] = once_value_3;
        fra.me.REG[5] = fra.me.REG[5];
-      /* ./compiling//compiling_icode.nit:44 */
+      /* compiling/compiling_icode.nit:45 */
        CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1], fra.me.REG[5]);
-      /* ./compiling//compiling_icode.nit:45 */
+      /* compiling/compiling_icode.nit:46 */
        fra.me.REG[2] = fra.me.REG[5];
        goto label2;
      } else {
-      /* ./compiling//compiling_icode.nit:49 */
+      /* compiling/compiling_icode.nit:50 */
        REGB0 = CALL_analysis___allocate_iregister_slots___IRegister___in_tag_slots(fra.me.REG[1])(fra.me.REG[1]);
        if (UNTAG_Bool(REGB0)) {
-        /* ./compiling//compiling_icode.nit:50 */
+        /* compiling/compiling_icode.nit:51 */
          if (!once_value_4) {
            fra.me.REG[5] = NEW_HashMap_standard___collection___hash_collection___HashMap___init();
            once_value_4 = fra.me.REG[5];
            register_static_object(&once_value_4);
          } else fra.me.REG[5] = once_value_4;
          fra.me.REG[5] = fra.me.REG[5];
-        /* ./compiling//compiling_icode.nit:51 */
+        /* compiling/compiling_icode.nit:52 */
          REGB0 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[4]);
          REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
          if (UNTAG_Bool(REGB0)) {
@@ -152,7 +153,7 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
            CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[4], fra.me.REG[6]);
          }
        } else {
-        /* ./compiling//compiling_icode.nit:52 */
+        /* compiling/compiling_icode.nit:53 */
          REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___closure(fra.me.REG[0])(fra.me.REG[0]);
          if (UNTAG_Bool(REGB0)) {
            REGB0 = CALL_analysis___allocate_iregister_slots___IRegister___is_local(fra.me.REG[1])(fra.me.REG[1]);
@@ -162,7 +163,7 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
            REGB0 = REGB1;
          }
          if (UNTAG_Bool(REGB0)) {
-          /* ./compiling//compiling_icode.nit:53 */
+          /* compiling/compiling_icode.nit:54 */
            if (!once_value_7) {
              fra.me.REG[0] = NEW_HashMap_standard___collection___hash_collection___HashMap___init();
              once_value_7 = fra.me.REG[0];
@@ -170,7 +171,7 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
            } else fra.me.REG[0] = once_value_7;
            fra.me.REG[0] = fra.me.REG[0];
            fra.me.REG[5] = fra.me.REG[0];
-          /* ./compiling//compiling_icode.nit:54 */
+          /* compiling/compiling_icode.nit:55 */
            REGB0 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[4]);
            REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
            if (UNTAG_Bool(REGB0)) {
@@ -200,7 +201,7 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
              CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[4], fra.me.REG[0]);
            }
          } else {
-          /* ./compiling//compiling_icode.nit:56 */
+          /* compiling/compiling_icode.nit:57 */
            if (!once_value_10) {
              fra.me.REG[0] = NEW_HashMap_standard___collection___hash_collection___HashMap___init();
              once_value_10 = fra.me.REG[0];
@@ -208,7 +209,7 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
            } else fra.me.REG[0] = once_value_10;
            fra.me.REG[0] = fra.me.REG[0];
            fra.me.REG[5] = fra.me.REG[0];
-          /* ./compiling//compiling_icode.nit:57 */
+          /* compiling/compiling_icode.nit:58 */
            REGB0 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[4]);
            REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
            if (UNTAG_Bool(REGB0)) {
@@ -239,11 +240,11 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register(val_t p0, val_
            }
          }
        }
-      /* ./compiling//compiling_icode.nit:59 */
+      /* compiling/compiling_icode.nit:60 */
        fra.me.REG[4] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[4]);
-      /* ./compiling//compiling_icode.nit:60 */
+      /* compiling/compiling_icode.nit:61 */
        CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1], fra.me.REG[4]);
-      /* ./compiling//compiling_icode.nit:61 */
+      /* compiling/compiling_icode.nit:62 */
        fra.me.REG[2] = fra.me.REG[4];
        goto label2;
      }
@@ -258,20 +259,21 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___registers(val_t p0, val
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 66;
+  fra.me.line = 67;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___registers;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:69 */
+  /* compiling/compiling_icode.nit:70 */
    REGB0 = CALL_standard___collection___abstract_collection___Collection___length(fra.me.REG[1])(fra.me.REG[1]);
    fra.me.REG[2] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    CALL_standard___collection___abstract_collection___Collection___iterate(fra.me.REG[1])(fra.me.REG[1], (&(fra.me)), ((fun_t)OC_compiling___compiling_icode___I2CCompilerVisitor___registers_1));
-  /* ./compiling//compiling_icode.nit:73 */
+  /* compiling/compiling_icode.nit:74 */
    goto label2;
    label2: while(0);
    stack_frame_head = fra.me.prev;
@@ -281,19 +283,20 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___registers(val_t p0, val
      struct {struct stack_frame_t me;} fra;
      fun_t CREG[1];
      val_t tmp;
-    /* ./compiling//compiling_icode.nit:70 */
+    /* compiling/compiling_icode.nit:71 */
      fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
      fra.me.file = LOCATE_compiling___compiling_icode;
      fra.me.line = 0;
      fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___registers;
      fra.me.has_broke = 0;
      fra.me.REG_size = 1;
+    fra.me.nitni_local_ref_head = NULL;
      fra.me.REG[0] = NIT_NULL;
      fra.me.closure_ctx = closctx_param;
      fra.me.closure_funs = CREG;
      fra.me.REG[0] = p0;
      CREG[0] = clos_fun0;
-    /* ./compiling//compiling_icode.nit:71 */
+    /* compiling/compiling_icode.nit:72 */
      fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(closctx->REG[0])(closctx->REG[0], fra.me.REG[0]);
      CALL_standard___collection___abstract_collection___SimpleCollection___add(closctx->REG[2])(closctx->REG[2], fra.me.REG[0]);
      stack_frame_head = fra.me.prev;
@@ -306,24 +309,25 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___new_number(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 77;
+  fra.me.line = 78;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___new_number;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:80 */
+  /* compiling/compiling_icode.nit:81 */
    REGB0 = ATTR_compiling___compiling_icode___I2CCompilerVisitor____last_number(fra.me.REG[0]);
    REGB1 = TAG_Int(1);
-  /* ./../lib/standard//kernel.nit:218 */
+  /* ../lib/standard/kernel.nit:235 */
    REGB1 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB1));
-  /* ./compiling//compiling_icode.nit:80 */
+  /* compiling/compiling_icode.nit:81 */
    ATTR_compiling___compiling_icode___I2CCompilerVisitor____last_number(fra.me.REG[0]) = REGB1;
-  /* ./compiling//compiling_icode.nit:81 */
+  /* compiling/compiling_icode.nit:82 */
    REGB1 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____last_number(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB1)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_last_number", LOCATE_compiling___compiling_icode, 81);
+    nit_abort("Uninitialized attribute %s", "_last_number", LOCATE_compiling___compiling_icode, 82);
    }
    REGB1 = ATTR_compiling___compiling_icode___I2CCompilerVisitor____last_number(fra.me.REG[0]);
    goto label1;
@@ -339,10 +343,11 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___lab(val_t p0, val_t p1)
      static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 84;
+  fra.me.line = 85;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___lab;
    fra.me.has_broke = 0;
    fra.me.REG_size = 5;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -350,26 +355,26 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___lab(val_t p0, val_t p1)
    fra.me.REG[4] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:87 */
+  /* compiling/compiling_icode.nit:88 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 87);
+    nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 88);
    }
    fra.me.REG[2] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0]);
    REGB0 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:88 */
+    /* compiling/compiling_icode.nit:89 */
      REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0])!=NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
      } else {
-      nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 88);
+      nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 89);
      }
      fra.me.REG[2] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0]);
      fra.me.REG[2] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
      goto label1;
    } else {
-    /* ./compiling//compiling_icode.nit:90 */
+    /* compiling/compiling_icode.nit:91 */
      REGB0 = TAG_Int(3);
      fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
      if (!once_value_2) {
@@ -394,15 +399,15 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___lab(val_t p0, val_t p1)
      fra.me.REG[4] = fra.me.REG[4];
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
      fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:91 */
+    /* compiling/compiling_icode.nit:92 */
      REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0])!=NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
      } else {
-      nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 91);
+      nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 92);
      }
      fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0]);
      CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:92 */
+    /* compiling/compiling_icode.nit:93 */
      fra.me.REG[2] = fra.me.REG[3];
      goto label1;
    }
@@ -416,17 +421,18 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___closures(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 96;
+  fra.me.line = 97;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___closures;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:96 */
+  /* compiling/compiling_icode.nit:97 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____closures(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_closures", LOCATE_compiling___compiling_icode, 96);
+    nit_abort("Uninitialized attribute %s", "_closures", LOCATE_compiling___compiling_icode, 97);
    }
    fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____closures(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -438,17 +444,18 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___clostypes(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 99;
+  fra.me.line = 100;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___clostypes;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:99 */
+  /* compiling/compiling_icode.nit:100 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____clostypes(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_clostypes", LOCATE_compiling___compiling_icode, 99);
+    nit_abort("Uninitialized attribute %s", "_clostypes", LOCATE_compiling___compiling_icode, 100);
    }
    fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____clostypes(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -460,17 +467,18 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___local_labels(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 102;
+  fra.me.line = 103;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___local_labels;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:102 */
+  /* compiling/compiling_icode.nit:103 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____local_labels(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_local_labels", LOCATE_compiling___compiling_icode, 102);
+    nit_abort("Uninitialized attribute %s", "_local_labels", LOCATE_compiling___compiling_icode, 103);
    }
    fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____local_labels(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -481,15 +489,16 @@ void compiling___compiling_icode___I2CCompilerVisitor___local_labels__eq(val_t p
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 102;
+  fra.me.line = 103;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___local_labels__eq;
    fra.me.has_broke = 0;
    fra.me.REG_size = 2;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:102 */
+  /* compiling/compiling_icode.nit:103 */
    ATTR_compiling___compiling_icode___I2CCompilerVisitor____local_labels(fra.me.REG[0]) = fra.me.REG[1];
    stack_frame_head = fra.me.prev;
    return;
@@ -500,17 +509,18 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___escaped_labels(val_t p0
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 105;
+  fra.me.line = 106;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:105 */
+  /* compiling/compiling_icode.nit:106 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 105);
+    nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 106);
    }
    fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -521,15 +531,16 @@ void compiling___compiling_icode___I2CCompilerVisitor___escaped_labels__eq(val_t
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 105;
+  fra.me.line = 106;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels__eq;
    fra.me.has_broke = 0;
    fra.me.REG_size = 2;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:105 */
+  /* compiling/compiling_icode.nit:106 */
    ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0]) = fra.me.REG[1];
    stack_frame_head = fra.me.prev;
    return;
@@ -542,55 +553,56 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___register_escape_label(v
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 109;
+  fra.me.line = 110;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___register_escape_label;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:112 */
+  /* compiling/compiling_icode.nit:113 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 112);
+    nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 113);
    }
    fra.me.REG[2] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0]);
    REGB0 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:113 */
+    /* compiling/compiling_icode.nit:114 */
      REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0])!=NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
      } else {
-      nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 113);
+      nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 114);
      }
      fra.me.REG[2] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0]);
      fra.me.REG[2] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
      REGB0 = fra.me.REG[2];
      goto label1;
    } else {
-    /* ./compiling//compiling_icode.nit:115 */
+    /* compiling/compiling_icode.nit:116 */
      REGB1 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0])!=NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
      } else {
-      nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 115);
+      nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 116);
      }
      fra.me.REG[2] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0]);
-    REGB1 = CALL_standard___collection___abstract_collection___Collection___length(fra.me.REG[2])(fra.me.REG[2]);
+    REGB1 = CALL_standard___collection___abstract_collection___MapRead___length(fra.me.REG[2])(fra.me.REG[2]);
      REGB2 = TAG_Int(1);
-    /* ./../lib/standard//kernel.nit:218 */
+    /* ../lib/standard/kernel.nit:235 */
      REGB2 = TAG_Int(UNTAG_Int(REGB1)+UNTAG_Int(REGB2));
-    /* ./compiling//compiling_icode.nit:116 */
+    /* compiling/compiling_icode.nit:117 */
      REGB1 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0])!=NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
      } else {
-      nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 116);
+      nit_abort("Uninitialized attribute %s", "_escaped_labels", LOCATE_compiling___compiling_icode, 117);
      }
      fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____escaped_labels(fra.me.REG[0]);
      CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1], REGB2);
-    /* ./compiling//compiling_icode.nit:117 */
+    /* compiling/compiling_icode.nit:118 */
      REGB0 = REGB2;
      goto label1;
    }
@@ -606,26 +618,27 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_label(val_t p0, val_
      static val_t once_value_2; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 121;
+  fra.me.line = 122;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___add_label;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:124 */
+  /* compiling/compiling_icode.nit:125 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 124);
+    nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 125);
    }
    fra.me.REG[2] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0]);
    REGB0 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:125 */
+    /* compiling/compiling_icode.nit:126 */
      REGB0 = TAG_Int(3);
      fra.me.REG[2] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
      if (!once_value_1) {
@@ -640,7 +653,7 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_label(val_t p0, val_
      REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0])!=NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
      } else {
-      nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 125);
+      nit_abort("Uninitialized attribute %s", "_ids", LOCATE_compiling___compiling_icode, 126);
      }
      fra.me.REG[3] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____ids(fra.me.REG[0]);
      fra.me.REG[1] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
@@ -661,7 +674,7 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_label(val_t p0, val_
    return;
  }
  void compiling___compiling_icode___I2CCompilerVisitor___add_goto(val_t p0, val_t p1){
-  struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[4];} fra;
    val_t REGB0;
    val_t REGB1;
    val_t tmp;
@@ -673,110 +686,114 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_goto(val_t p0, val_t
      static val_t once_value_6; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 129;
+  fra.me.line = 130;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___add_goto;
    fra.me.has_broke = 0;
-  fra.me.REG_size = 4;
+  fra.me.REG_size = 5;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
+  fra.me.REG[4] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:132 */
-  fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___local_labels(fra.me.REG[0])(fra.me.REG[0]);
-  REGB0 = CALL_standard___collection___abstract_collection___Collection___has(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+  /* compiling/compiling_icode.nit:130 */
+  fra.me.REG[2] = fra.me.REG[0];
+  /* compiling/compiling_icode.nit:133 */
+  fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___local_labels(fra.me.REG[2])(fra.me.REG[2]);
+  REGB0 = CALL_standard___collection___abstract_collection___Collection___has(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:133 */
+    /* compiling/compiling_icode.nit:134 */
      REGB0 = TAG_Int(3);
-    fra.me.REG[2] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
+    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
      if (!once_value_1) {
-      fra.me.REG[3] = BOX_NativeString("goto ");
+      fra.me.REG[4] = BOX_NativeString("goto ");
        REGB0 = TAG_Int(5);
-      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-      once_value_1 = fra.me.REG[3];
+      fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+      once_value_1 = fra.me.REG[4];
        register_static_object(&once_value_1);
-    } else fra.me.REG[3] = once_value_1;
-    fra.me.REG[3] = fra.me.REG[3];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-    fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___lab(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
+    } else fra.me.REG[4] = once_value_1;
+    fra.me.REG[4] = fra.me.REG[4];
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    fra.me.REG[4] = CALL_compiling___compiling_icode___I2CCompilerVisitor___lab(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
      if (!once_value_2) {
-      fra.me.REG[3] = BOX_NativeString(";");
+      fra.me.REG[4] = BOX_NativeString(";");
        REGB0 = TAG_Int(1);
-      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-      once_value_2 = fra.me.REG[3];
+      fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+      once_value_2 = fra.me.REG[4];
        register_static_object(&once_value_2);
-    } else fra.me.REG[3] = once_value_2;
-    fra.me.REG[3] = fra.me.REG[3];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-    fra.me.REG[2] = CALL_standard___string___Object___to_s(fra.me.REG[2])(fra.me.REG[2]);
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[2]);
+    } else fra.me.REG[4] = once_value_2;
+    fra.me.REG[4] = fra.me.REG[4];
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
    } else {
-    /* ./compiling//compiling_icode.nit:135 */
-    REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___closure(fra.me.REG[0])(fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:136 */
+    REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___closure(fra.me.REG[2])(fra.me.REG[2]);
      if (UNTAG_Bool(REGB0)) {
      } else {
-      nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 135);
+      nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 136);
      }
-    /* ./compiling//compiling_icode.nit:136 */
-    REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___register_escape_label(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:137 */
+    /* compiling/compiling_icode.nit:137 */
+    REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___register_escape_label(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+    /* compiling/compiling_icode.nit:138 */
      REGB1 = TAG_Int(3);
      fra.me.REG[1] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
      if (!once_value_3) {
-      fra.me.REG[2] = BOX_NativeString("closctx->has_broke = ");
+      fra.me.REG[3] = BOX_NativeString("closctx->has_broke = ");
        REGB1 = TAG_Int(21);
-      fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-      once_value_3 = fra.me.REG[2];
+      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB1);
+      once_value_3 = fra.me.REG[3];
        register_static_object(&once_value_3);
-    } else fra.me.REG[2] = once_value_3;
-    fra.me.REG[2] = fra.me.REG[2];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-    fra.me.REG[2] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
+    } else fra.me.REG[3] = once_value_3;
+    fra.me.REG[3] = fra.me.REG[3];
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+    fra.me.REG[3] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
      if (!once_value_4) {
-      fra.me.REG[2] = BOX_NativeString(";");
+      fra.me.REG[3] = BOX_NativeString(";");
        REGB0 = TAG_Int(1);
-      fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
-      once_value_4 = fra.me.REG[2];
+      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+      once_value_4 = fra.me.REG[3];
        register_static_object(&once_value_4);
-    } else fra.me.REG[2] = once_value_4;
-    fra.me.REG[2] = fra.me.REG[2];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
+    } else fra.me.REG[3] = once_value_4;
+    fra.me.REG[3] = fra.me.REG[3];
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
      fra.me.REG[1] = CALL_standard___string___Object___to_s(fra.me.REG[1])(fra.me.REG[1]);
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:138 */
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+    /* compiling/compiling_icode.nit:139 */
      REGB0 = TAG_Int(3);
      fra.me.REG[1] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
      if (!once_value_5) {
-      fra.me.REG[2] = BOX_NativeString("goto ");
+      fra.me.REG[3] = BOX_NativeString("goto ");
        REGB0 = TAG_Int(5);
-      fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
-      once_value_5 = fra.me.REG[2];
+      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+      once_value_5 = fra.me.REG[3];
        register_static_object(&once_value_5);
-    } else fra.me.REG[2] = once_value_5;
-    fra.me.REG[2] = fra.me.REG[2];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___return_label(fra.me.REG[0])(fra.me.REG[0]);
-    REGB0 = TAG_Bool(fra.me.REG[2]!=NIT_NULL);
+    } else fra.me.REG[3] = once_value_5;
+    fra.me.REG[3] = fra.me.REG[3];
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+    fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___return_label(fra.me.REG[2])(fra.me.REG[2]);
+    REGB0 = TAG_Bool(fra.me.REG[3]!=NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
      } else {
-      nit_abort("Cast failed", NULL, LOCATE_compiling___compiling_icode, 138);
+      nit_abort("Cast failed", NULL, LOCATE_compiling___compiling_icode, 139);
      }
-    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___lab(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[2]);
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
+    fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___lab(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
      if (!once_value_6) {
-      fra.me.REG[2] = BOX_NativeString(";");
+      fra.me.REG[3] = BOX_NativeString(";");
        REGB0 = TAG_Int(1);
-      fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
-      once_value_6 = fra.me.REG[2];
+      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+      once_value_6 = fra.me.REG[3];
        register_static_object(&once_value_6);
-    } else fra.me.REG[2] = once_value_6;
-    fra.me.REG[2] = fra.me.REG[2];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
+    } else fra.me.REG[3] = once_value_6;
+    fra.me.REG[3] = fra.me.REG[3];
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
      fra.me.REG[1] = CALL_standard___string___Object___to_s(fra.me.REG[1])(fra.me.REG[1]);
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
    }
    stack_frame_head = fra.me.prev;
    return;
@@ -787,17 +804,18 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___marks_to_seq(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 142;
+  fra.me.line = 143;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___marks_to_seq;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:142 */
+  /* compiling/compiling_icode.nit:143 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____marks_to_seq(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_marks_to_seq", LOCATE_compiling___compiling_icode, 142);
+    nit_abort("Uninitialized attribute %s", "_marks_to_seq", LOCATE_compiling___compiling_icode, 143);
    }
    fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____marks_to_seq(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -809,17 +827,18 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___closure(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 145;
+  fra.me.line = 146;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___closure;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:145 */
+  /* compiling/compiling_icode.nit:146 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____closure(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_closure", LOCATE_compiling___compiling_icode, 145);
+    nit_abort("Uninitialized attribute %s", "_closure", LOCATE_compiling___compiling_icode, 146);
    }
    REGB0 = ATTR_compiling___compiling_icode___I2CCompilerVisitor____closure(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -831,14 +850,15 @@ void compiling___compiling_icode___I2CCompilerVisitor___closure__eq(val_t p0, va
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 145;
+  fra.me.line = 146;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___closure__eq;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
    REGB0 = p1;
-  /* ./compiling//compiling_icode.nit:145 */
+  /* compiling/compiling_icode.nit:146 */
    ATTR_compiling___compiling_icode___I2CCompilerVisitor____closure(fra.me.REG[0]) = REGB0;
    stack_frame_head = fra.me.prev;
    return;
@@ -849,17 +869,18 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___visitor(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 148;
+  fra.me.line = 149;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___visitor;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:148 */
+  /* compiling/compiling_icode.nit:149 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____visitor(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_visitor", LOCATE_compiling___compiling_icode, 148);
+    nit_abort("Uninitialized attribute %s", "_visitor", LOCATE_compiling___compiling_icode, 149);
    }
    fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____visitor(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -871,17 +892,18 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___iroutine(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 151;
+  fra.me.line = 152;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___iroutine;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:151 */
+  /* compiling/compiling_icode.nit:152 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____iroutine(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_iroutine", LOCATE_compiling___compiling_icode, 151);
+    nit_abort("Uninitialized attribute %s", "_iroutine", LOCATE_compiling___compiling_icode, 152);
    }
    fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____iroutine(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -892,13 +914,14 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___return_label(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 154;
+  fra.me.line = 155;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___return_label;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:154 */
+  /* compiling/compiling_icode.nit:155 */
    fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____return_label(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
    return fra.me.REG[0];
@@ -908,15 +931,16 @@ void compiling___compiling_icode___I2CCompilerVisitor___return_label__eq(val_t p
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 154;
+  fra.me.line = 155;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___return_label__eq;
    fra.me.has_broke = 0;
    fra.me.REG_size = 2;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:154 */
+  /* compiling/compiling_icode.nit:155 */
    ATTR_compiling___compiling_icode___I2CCompilerVisitor____return_label(fra.me.REG[0]) = fra.me.REG[1];
    stack_frame_head = fra.me.prev;
    return;
@@ -926,15 +950,16 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_decl(val_t p0, val_t
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 157;
+  fra.me.line = 158;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___add_decl;
    fra.me.has_broke = 0;
    fra.me.REG_size = 2;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:159 */
+  /* compiling/compiling_icode.nit:160 */
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___visitor(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_base___CompilerVisitor___add_decl(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
    stack_frame_head = fra.me.prev;
@@ -950,21 +975,22 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___new_instr(val_t p0){
      static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 162;
+  fra.me.line = 163;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___new_instr;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:166 */
+  /* compiling/compiling_icode.nit:167 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___I2CCompilerVisitor___visitor(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[1] = CALL_compiling___compiling_base___CompilerVisitor___writer(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:167 */
+  /* compiling/compiling_icode.nit:168 */
    fra.me.REG[2] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____next_location(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:168 */
+  /* compiling/compiling_icode.nit:169 */
    REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -979,10 +1005,10 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___new_instr(val_t p0){
    }
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:169 */
+    /* compiling/compiling_icode.nit:170 */
      fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___visitor(fra.me.REG[0])(fra.me.REG[0]);
      CALL_compiling___compiling_base___CompilerVisitor___add_indent(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:170 */
+    /* compiling/compiling_icode.nit:171 */
      if (!once_value_1) {
        fra.me.REG[3] = BOX_NativeString("/* ");
        REGB0 = TAG_Int(3);
@@ -992,19 +1018,19 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___new_instr(val_t p0){
      } else fra.me.REG[3] = once_value_1;
      fra.me.REG[3] = fra.me.REG[3];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:171 */
+    /* compiling/compiling_icode.nit:172 */
      REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 171);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 172);
      }
      fra.me.REG[3] = CALL_location___Location___file(fra.me.REG[2])(fra.me.REG[2]);
      REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 171);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 172);
      }
      fra.me.REG[3] = CALL_location___SourceFile___filename(fra.me.REG[3])(fra.me.REG[3]);
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:172 */
+    /* compiling/compiling_icode.nit:173 */
      if (!once_value_2) {
        fra.me.REG[3] = BOX_NativeString(":");
        REGB0 = TAG_Int(1);
@@ -1014,15 +1040,15 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___new_instr(val_t p0){
      } else fra.me.REG[3] = once_value_2;
      fra.me.REG[3] = fra.me.REG[3];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:173 */
+    /* compiling/compiling_icode.nit:174 */
      REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 173);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 174);
      }
      REGB0 = CALL_location___Location___line_start(fra.me.REG[2])(fra.me.REG[2]);
      fra.me.REG[2] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-    /* ./compiling//compiling_icode.nit:174 */
+    /* compiling/compiling_icode.nit:175 */
      if (!once_value_3) {
        fra.me.REG[2] = BOX_NativeString(" */\n");
        REGB0 = TAG_Int(4);
@@ -1032,13 +1058,13 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___new_instr(val_t p0){
      } else fra.me.REG[2] = once_value_3;
      fra.me.REG[2] = fra.me.REG[2];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-    /* ./compiling//compiling_icode.nit:175 */
+    /* compiling/compiling_icode.nit:176 */
      ATTR_compiling___compiling_icode___I2CCompilerVisitor____next_location(fra.me.REG[0]) = NIT_NULL;
    }
-  /* ./compiling//compiling_icode.nit:177 */
+  /* compiling/compiling_icode.nit:178 */
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___visitor(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_base___CompilerVisitor___add_indent(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:178 */
+  /* compiling/compiling_icode.nit:179 */
    goto label4;
    label4: while(0);
    stack_frame_head = fra.me.prev;
@@ -1051,15 +1077,16 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_instr(val_t p0, val_
    static val_t once_value_1; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 181;
+  fra.me.line = 182;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___add_instr;
    fra.me.has_broke = 0;
    fra.me.REG_size = 2;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:183 */
+  /* compiling/compiling_icode.nit:184 */
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[1] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
    if (!once_value_1) {
@@ -1079,13 +1106,14 @@ void compiling___compiling_icode___I2CCompilerVisitor___indent(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 186;
+  fra.me.line = 187;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___indent;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:188 */
+  /* compiling/compiling_icode.nit:189 */
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___visitor(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_base___CompilerVisitor___indent(fra.me.REG[0])(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -1096,13 +1124,14 @@ void compiling___compiling_icode___I2CCompilerVisitor___unindent(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 191;
+  fra.me.line = 192;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___unindent;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:193 */
+  /* compiling/compiling_icode.nit:194 */
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___visitor(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_base___CompilerVisitor___unindent(fra.me.REG[0])(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -1113,17 +1142,18 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_assignment(val_t p0,
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 196;
+  fra.me.line = 197;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___add_assignment;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
    fra.me.REG[2] = p2;
-  /* ./compiling//compiling_icode.nit:198 */
+  /* compiling/compiling_icode.nit:199 */
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___visitor(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_base___CompilerVisitor___add_assignment(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1], fra.me.REG[2]);
    stack_frame_head = fra.me.prev;
@@ -1137,10 +1167,11 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_location(val_t p0, v
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 204;
+  fra.me.line = 205;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___add_location;
    fra.me.has_broke = 0;
    fra.me.REG_size = 5;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -1148,9 +1179,9 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_location(val_t p0, v
    fra.me.REG[4] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:208 */
+  /* compiling/compiling_icode.nit:209 */
    fra.me.REG[2] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____last_location(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:209 */
+  /* compiling/compiling_icode.nit:210 */
    REGB0 = TAG_Bool(IS_EQUAL_NN(fra.me.REG[2],fra.me.REG[1]));
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -1183,9 +1214,9 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_location(val_t p0, v
    if (UNTAG_Bool(REGB0)) {
      goto label1;
    }
-  /* ./compiling//compiling_icode.nit:210 */
+  /* compiling/compiling_icode.nit:211 */
    ATTR_compiling___compiling_icode___I2CCompilerVisitor____last_location(fra.me.REG[0]) = fra.me.REG[1];
-  /* ./compiling//compiling_icode.nit:211 */
+  /* compiling/compiling_icode.nit:212 */
    REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -1202,12 +1233,12 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_location(val_t p0, v
    if (UNTAG_Bool(REGB0)) {
      REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 211);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 212);
      }
      fra.me.REG[3] = CALL_location___Location___file(fra.me.REG[2])(fra.me.REG[2]);
      REGB0 = TAG_Bool(fra.me.REG[1]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 211);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 212);
      }
      fra.me.REG[4] = CALL_location___Location___file(fra.me.REG[1])(fra.me.REG[1]);
      REGB0 = TAG_Bool(IS_EQUAL_NN(fra.me.REG[3],fra.me.REG[4]));
@@ -1229,20 +1260,20 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_location(val_t p0, v
    if (UNTAG_Bool(REGB0)) {
      REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 211);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 212);
      }
      REGB0 = CALL_location___Location___line_start(fra.me.REG[2])(fra.me.REG[2]);
      REGB1 = TAG_Bool(fra.me.REG[1]==NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 211);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 212);
      }
      REGB1 = CALL_location___Location___line_start(fra.me.REG[1])(fra.me.REG[1]);
      REGB2 = TAG_Bool(IS_EQUAL_OO(REGB0,REGB1));
      if (UNTAG_Bool(REGB2)) {
      } else {
-      /* ./../lib/standard//kernel.nit:210 */
+      /* ../lib/standard/kernel.nit:227 */
        REGB1 = TAG_Bool((REGB0)==(REGB1));
-      /* ./compiling//compiling_icode.nit:211 */
+      /* compiling/compiling_icode.nit:212 */
        REGB2 = REGB1;
      }
    } else {
@@ -1250,10 +1281,10 @@ void compiling___compiling_icode___I2CCompilerVisitor___add_location(val_t p0, v
      REGB2 = REGB1;
    }
    if (UNTAG_Bool(REGB2)) {
-    /* ./compiling//compiling_icode.nit:212 */
+    /* compiling/compiling_icode.nit:213 */
      goto label1;
    } else {
-    /* ./compiling//compiling_icode.nit:214 */
+    /* compiling/compiling_icode.nit:215 */
      ATTR_compiling___compiling_icode___I2CCompilerVisitor____next_location(fra.me.REG[0]) = fra.me.REG[1];
    }
    label1: while(0);
@@ -1266,17 +1297,18 @@ val_t compiling___compiling_icode___I2CCompilerVisitor___basecname(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 218;
+  fra.me.line = 219;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___basecname;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:218 */
+  /* compiling/compiling_icode.nit:219 */
    REGB0 = TAG_Bool(ATTR_compiling___compiling_icode___I2CCompilerVisitor____basecname(fra.me.REG[0])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_basecname", LOCATE_compiling___compiling_icode, 218);
+    nit_abort("Uninitialized attribute %s", "_basecname", LOCATE_compiling___compiling_icode, 219);
    }
    fra.me.REG[0] = ATTR_compiling___compiling_icode___I2CCompilerVisitor____basecname(fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
@@ -1289,10 +1321,11 @@ void compiling___compiling_icode___I2CCompilerVisitor___init(val_t p0, val_t p1,
    if (init_table[itpos0]) return;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 221;
+  fra.me.line = 222;
    fra.me.meth = LOCATE_compiling___compiling_icode___I2CCompilerVisitor___init;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -1301,11 +1334,11 @@ void compiling___compiling_icode___I2CCompilerVisitor___init(val_t p0, val_t p1,
    fra.me.REG[1] = p1;
    fra.me.REG[2] = p2;
    fra.me.REG[3] = p3;
-  /* ./compiling//compiling_icode.nit:223 */
+  /* compiling/compiling_icode.nit:224 */
    ATTR_compiling___compiling_icode___I2CCompilerVisitor____visitor(fra.me.REG[0]) = fra.me.REG[1];
-  /* ./compiling//compiling_icode.nit:224 */
+  /* compiling/compiling_icode.nit:225 */
    ATTR_compiling___compiling_icode___I2CCompilerVisitor____iroutine(fra.me.REG[0]) = fra.me.REG[2];
-  /* ./compiling//compiling_icode.nit:225 */
+  /* compiling/compiling_icode.nit:226 */
    ATTR_compiling___compiling_icode___I2CCompilerVisitor____basecname(fra.me.REG[0]) = fra.me.REG[3];
    stack_frame_head = fra.me.prev;
    init_table[itpos0] = 1;
@@ -1362,10 +1395,11 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
    static val_t once_value_43; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 230;
+  fra.me.line = 231;
    fra.me.meth = LOCATE_compiling___compiling_icode___IRoutine___compile_signature_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 12;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -1384,11 +1418,11 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
    fra.me.REG[3] = p3;
    fra.me.REG[4] = p4;
    fra.me.REG[5] = p5;
-  /* ./compiling//compiling_icode.nit:236 */
+  /* compiling/compiling_icode.nit:237 */
    fra.me.REG[6] = NEW_Array_standard___collection___array___Array___init();
-  /* ./compiling//compiling_icode.nit:237 */
+  /* compiling/compiling_icode.nit:238 */
    fra.me.REG[7] = NEW_Array_standard___collection___array___Array___init();
-  /* ./compiling//compiling_icode.nit:238 */
+  /* compiling/compiling_icode.nit:239 */
    REGB0 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -1405,19 +1439,24 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
    if (UNTAG_Bool(REGB0)) {
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[4]);
    }
-  /* ./compiling//compiling_icode.nit:239 */
+  /* compiling/compiling_icode.nit:240 */
    REGB0 = TAG_Int(0);
    fra.me.REG[4] = CALL_icode___icode_base___IRoutine___params(fra.me.REG[0])(fra.me.REG[0]);
    REGB1 = CALL_standard___collection___abstract_collection___Collection___length(fra.me.REG[4])(fra.me.REG[4]);
-  /* ./../lib/standard//kernel.nit:335 */
+  /* ../lib/standard/kernel.nit:352 */
    while(1) {
-    /* ./../lib/standard//kernel.nit:215 */
+    REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+    if (UNTAG_Bool(REGB2)) {
+    } else {
+      nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+    }
+    /* ../lib/standard/kernel.nit:232 */
      REGB2 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
-    /* ./../lib/standard//kernel.nit:335 */
+    /* ../lib/standard/kernel.nit:352 */
      if (UNTAG_Bool(REGB2)) {
-      /* ./compiling//compiling_icode.nit:239 */
+      /* compiling/compiling_icode.nit:240 */
        REGB2 = REGB0;
-      /* ./compiling//compiling_icode.nit:240 */
+      /* compiling/compiling_icode.nit:241 */
        REGB3 = TAG_Int(3);
        fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB3);
        if (!once_value_1) {
@@ -1442,7 +1481,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[8]);
        fra.me.REG[4] = CALL_standard___string___Object___to_s(fra.me.REG[4])(fra.me.REG[4]);
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[4]);
-      /* ./compiling//compiling_icode.nit:241 */
+      /* compiling/compiling_icode.nit:242 */
        REGB3 = TAG_Int(3);
        fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB3);
        if (!once_value_3) {
@@ -1467,19 +1506,19 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[8]);
        fra.me.REG[4] = CALL_standard___string___Object___to_s(fra.me.REG[4])(fra.me.REG[4]);
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[4]);
-      /* ./../lib/standard//kernel.nit:337 */
+      /* ../lib/standard/kernel.nit:354 */
        REGB2 = TAG_Int(1);
-      /* ./../lib/standard//kernel.nit:218 */
+      /* ../lib/standard/kernel.nit:235 */
        REGB2 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB2));
-      /* ./../lib/standard//kernel.nit:337 */
+      /* ../lib/standard/kernel.nit:354 */
        REGB0 = REGB2;
      } else {
-      /* ./../lib/standard//kernel.nit:335 */
+      /* ../lib/standard/kernel.nit:352 */
        goto label5;
      }
    }
    label5: while(0);
-  /* ./compiling//compiling_icode.nit:243 */
+  /* compiling/compiling_icode.nit:244 */
    fra.me.REG[4] = CALL_icode___icode_base___IRoutine___closure_decls(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
@@ -1495,7 +1534,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
    }
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:244 */
+    /* compiling/compiling_icode.nit:245 */
      if (!once_value_6) {
        fra.me.REG[4] = BOX_NativeString("struct stack_frame_t *closctx_param");
        REGB0 = TAG_Int(35);
@@ -1505,23 +1544,28 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
      } else fra.me.REG[4] = once_value_6;
      fra.me.REG[4] = fra.me.REG[4];
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[4]);
-    /* ./compiling//compiling_icode.nit:245 */
+    /* compiling/compiling_icode.nit:246 */
      REGB0 = TAG_Int(0);
      fra.me.REG[4] = CALL_icode___icode_base___IRoutine___closure_decls(fra.me.REG[0])(fra.me.REG[0]);
      REGB1 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 245);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 246);
      }
      REGB1 = CALL_standard___collection___abstract_collection___Collection___length(fra.me.REG[4])(fra.me.REG[4]);
-    /* ./../lib/standard//kernel.nit:335 */
+    /* ../lib/standard/kernel.nit:352 */
      while(1) {
-      /* ./../lib/standard//kernel.nit:215 */
+      REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+      if (UNTAG_Bool(REGB2)) {
+      } else {
+        nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+      }
+      /* ../lib/standard/kernel.nit:232 */
        REGB2 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
-      /* ./../lib/standard//kernel.nit:335 */
+      /* ../lib/standard/kernel.nit:352 */
        if (UNTAG_Bool(REGB2)) {
-        /* ./compiling//compiling_icode.nit:245 */
+        /* compiling/compiling_icode.nit:246 */
          REGB2 = REGB0;
-        /* ./compiling//compiling_icode.nit:246 */
+        /* compiling/compiling_icode.nit:247 */
          REGB3 = TAG_Int(5);
          fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB3);
          if (!once_value_7) {
@@ -1555,22 +1599,22 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
          fra.me.REG[8] = fra.me.REG[8];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[8]);
          fra.me.REG[4] = CALL_standard___string___Object___to_s(fra.me.REG[4])(fra.me.REG[4]);
-        /* ./compiling//compiling_icode.nit:247 */
+        /* compiling/compiling_icode.nit:248 */
          fra.me.REG[8] = CALL_icode___icode_base___IRoutine___closure_decls(fra.me.REG[0])(fra.me.REG[0]);
          REGB3 = TAG_Bool(fra.me.REG[8]==NIT_NULL);
          if (UNTAG_Bool(REGB3)) {
-          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 247);
+          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 248);
          }
-        fra.me.REG[8] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[8])(fra.me.REG[8], REGB2);
+        fra.me.REG[8] = CALL_standard___collection___abstract_collection___SequenceRead_____bra(fra.me.REG[8])(fra.me.REG[8], REGB2);
          REGB3 = TAG_Bool(fra.me.REG[8]==NIT_NULL);
          if (UNTAG_Bool(REGB3)) {
-          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 247);
+          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 248);
          }
          fra.me.REG[8] = CALL_icode___icode_base___IClosureDecl___closure(fra.me.REG[8])(fra.me.REG[8]);
          fra.me.REG[8] = CALL_metamodel___static_type___MMClosure___signature(fra.me.REG[8])(fra.me.REG[8]);
-        /* ./compiling//compiling_icode.nit:248 */
+        /* compiling/compiling_icode.nit:249 */
          fra.me.REG[9] = NEW_Array_standard___collection___array___Array___init();
-        /* ./compiling//compiling_icode.nit:249 */
+        /* compiling/compiling_icode.nit:250 */
          if (!once_value_10) {
            fra.me.REG[10] = BOX_NativeString("struct stack_frame_t *");
            REGB3 = TAG_Int(22);
@@ -1580,16 +1624,21 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
          } else fra.me.REG[10] = once_value_10;
          fra.me.REG[10] = fra.me.REG[10];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[9])(fra.me.REG[9], fra.me.REG[10]);
-        /* ./compiling//compiling_icode.nit:250 */
+        /* compiling/compiling_icode.nit:251 */
          REGB3 = TAG_Int(0);
          REGB4 = CALL_metamodel___static_type___MMSignature___arity(fra.me.REG[8])(fra.me.REG[8]);
-        /* ./../lib/standard//kernel.nit:335 */
+        /* ../lib/standard/kernel.nit:352 */
          while(1) {
-          /* ./../lib/standard//kernel.nit:215 */
+          REGB5 = TAG_Bool(VAL_ISA(REGB4, VTCOLOR_standard___kernel___Comparable___OTHER(REGB3), VTID_standard___kernel___Comparable___OTHER(REGB3))) /*cast OTHER*/;
+          if (UNTAG_Bool(REGB5)) {
+          } else {
+            nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+          }
+          /* ../lib/standard/kernel.nit:232 */
            REGB5 = TAG_Bool(UNTAG_Int(REGB3)<UNTAG_Int(REGB4));
-          /* ./../lib/standard//kernel.nit:335 */
+          /* ../lib/standard/kernel.nit:352 */
            if (UNTAG_Bool(REGB5)) {
-            /* ./compiling//compiling_icode.nit:251 */
+            /* compiling/compiling_icode.nit:252 */
              if (!once_value_11) {
                fra.me.REG[10] = BOX_NativeString("val_t");
                REGB5 = TAG_Int(5);
@@ -1599,19 +1648,19 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
              } else fra.me.REG[10] = once_value_11;
              fra.me.REG[10] = fra.me.REG[10];
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[9])(fra.me.REG[9], fra.me.REG[10]);
-            /* ./../lib/standard//kernel.nit:337 */
+            /* ../lib/standard/kernel.nit:354 */
              REGB5 = TAG_Int(1);
-            /* ./../lib/standard//kernel.nit:218 */
+            /* ../lib/standard/kernel.nit:235 */
              REGB5 = TAG_Int(UNTAG_Int(REGB3)+UNTAG_Int(REGB5));
-            /* ./../lib/standard//kernel.nit:337 */
+            /* ../lib/standard/kernel.nit:354 */
              REGB3 = REGB5;
            } else {
-            /* ./../lib/standard//kernel.nit:335 */
+            /* ../lib/standard/kernel.nit:352 */
              goto label12;
            }
          }
          label12: while(0);
-        /* ./compiling//compiling_icode.nit:253 */
+        /* compiling/compiling_icode.nit:254 */
          if (!once_value_13) {
            fra.me.REG[10] = BOX_NativeString("void");
            REGB3 = TAG_Int(4);
@@ -1620,7 +1669,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
            register_static_object(&once_value_13);
          } else fra.me.REG[10] = once_value_13;
          fra.me.REG[10] = fra.me.REG[10];
-        /* ./compiling//compiling_icode.nit:254 */
+        /* compiling/compiling_icode.nit:255 */
          fra.me.REG[8] = CALL_metamodel___static_type___MMSignature___return_type(fra.me.REG[8])(fra.me.REG[8]);
          REGB3 = TAG_Bool(fra.me.REG[8]==NIT_NULL);
          if (UNTAG_Bool(REGB3)) {
@@ -1646,7 +1695,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
            fra.me.REG[8] = fra.me.REG[8];
            fra.me.REG[10] = fra.me.REG[8];
          }
-        /* ./compiling//compiling_icode.nit:255 */
+        /* compiling/compiling_icode.nit:256 */
          REGB3 = TAG_Int(7);
          fra.me.REG[8] = NEW_Array_standard___collection___array___Array___with_capacity(REGB3);
          if (!once_value_15) {
@@ -1699,7 +1748,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[4]);
          fra.me.REG[8] = CALL_standard___string___Object___to_s(fra.me.REG[8])(fra.me.REG[8]);
          CALL_compiling___compiling_base___CompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[8]);
-        /* ./compiling//compiling_icode.nit:256 */
+        /* compiling/compiling_icode.nit:257 */
          REGB3 = TAG_Int(3);
          fra.me.REG[8] = NEW_Array_standard___collection___array___Array___with_capacity(REGB3);
          if (!once_value_20) {
@@ -1724,7 +1773,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[4]);
          fra.me.REG[8] = CALL_standard___string___Object___to_s(fra.me.REG[8])(fra.me.REG[8]);
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[8]);
-        /* ./compiling//compiling_icode.nit:257 */
+        /* compiling/compiling_icode.nit:258 */
          REGB3 = TAG_Int(3);
          fra.me.REG[8] = NEW_Array_standard___collection___array___Array___with_capacity(REGB3);
          if (!once_value_22) {
@@ -1749,20 +1798,20 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[4]);
          fra.me.REG[8] = CALL_standard___string___Object___to_s(fra.me.REG[8])(fra.me.REG[8]);
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[8]);
-        /* ./../lib/standard//kernel.nit:337 */
+        /* ../lib/standard/kernel.nit:354 */
          REGB2 = TAG_Int(1);
-        /* ./../lib/standard//kernel.nit:218 */
+        /* ../lib/standard/kernel.nit:235 */
          REGB2 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB2));
-        /* ./../lib/standard//kernel.nit:337 */
+        /* ../lib/standard/kernel.nit:354 */
          REGB0 = REGB2;
        } else {
-        /* ./../lib/standard//kernel.nit:335 */
+        /* ../lib/standard/kernel.nit:352 */
          goto label24;
        }
      }
      label24: while(0);
    }
-  /* ./compiling//compiling_icode.nit:260 */
+  /* compiling/compiling_icode.nit:261 */
    REGB0 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -1779,7 +1828,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
    if (UNTAG_Bool(REGB0)) {
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[5]);
    }
-  /* ./compiling//compiling_icode.nit:261 */
+  /* compiling/compiling_icode.nit:262 */
    if (!once_value_25) {
      fra.me.REG[5] = BOX_NativeString("void");
      REGB0 = TAG_Int(4);
@@ -1788,7 +1837,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
      register_static_object(&once_value_25);
    } else fra.me.REG[5] = once_value_25;
    fra.me.REG[5] = fra.me.REG[5];
-  /* ./compiling//compiling_icode.nit:262 */
+  /* compiling/compiling_icode.nit:263 */
    fra.me.REG[0] = CALL_icode___icode_base___IRoutine___result(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
@@ -1814,10 +1863,10 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
      fra.me.REG[0] = fra.me.REG[0];
      fra.me.REG[5] = fra.me.REG[0];
    }
-  /* ./compiling//compiling_icode.nit:264 */
+  /* compiling/compiling_icode.nit:265 */
    REGB0 = CALL_standard___collection___abstract_collection___Collection___is_empty(fra.me.REG[7])(fra.me.REG[7]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:265 */
+    /* compiling/compiling_icode.nit:266 */
      if (!once_value_27) {
        fra.me.REG[0] = BOX_NativeString("void");
        REGB0 = TAG_Int(4);
@@ -1827,7 +1876,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
      } else fra.me.REG[0] = once_value_27;
      fra.me.REG[0] = fra.me.REG[0];
    } else {
-    /* ./compiling//compiling_icode.nit:267 */
+    /* compiling/compiling_icode.nit:268 */
      if (!once_value_28) {
        fra.me.REG[8] = BOX_NativeString(", ");
        REGB0 = TAG_Int(2);
@@ -1839,7 +1888,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
      fra.me.REG[8] = CALL_standard___string___Collection___join(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[8]);
      fra.me.REG[0] = fra.me.REG[8];
    }
-  /* ./compiling//compiling_icode.nit:269 */
+  /* compiling/compiling_icode.nit:270 */
    REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -1888,7 +1937,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
      fra.me.REG[8] = CALL_standard___string___Object___to_s(fra.me.REG[8])(fra.me.REG[8]);
      CALL_compiling___compiling_base___CompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[8]);
    }
-  /* ./compiling//compiling_icode.nit:270 */
+  /* compiling/compiling_icode.nit:271 */
    REGB0 = TAG_Int(7);
    fra.me.REG[8] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    if (!once_value_32) {
@@ -1932,7 +1981,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[3]);
    fra.me.REG[8] = CALL_standard___string___Object___to_s(fra.me.REG[8])(fra.me.REG[8]);
    CALL_compiling___compiling_base___CompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[8]);
-  /* ./compiling//compiling_icode.nit:271 */
+  /* compiling/compiling_icode.nit:272 */
    REGB0 = TAG_Int(7);
    fra.me.REG[8] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    if (!once_value_36) {
@@ -1976,7 +2025,7 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[3]);
    fra.me.REG[8] = CALL_standard___string___Object___to_s(fra.me.REG[8])(fra.me.REG[8]);
    CALL_compiling___compiling_base___CompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[8]);
-  /* ./compiling//compiling_icode.nit:272 */
+  /* compiling/compiling_icode.nit:273 */
    REGB0 = TAG_Int(7);
    fra.me.REG[8] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    if (!once_value_40) {
@@ -2020,9 +2069,9 @@ val_t compiling___compiling_icode___IRoutine___compile_signature_to_c(val_t p0,
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[0]);
    fra.me.REG[8] = CALL_standard___string___Object___to_s(fra.me.REG[8])(fra.me.REG[8]);
    CALL_compiling___compiling_base___CompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[8]);
-  /* ./compiling//compiling_icode.nit:273 */
+  /* compiling/compiling_icode.nit:274 */
    CALL_compiling___compiling_base___CompilerVisitor___indent(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:274 */
+  /* compiling/compiling_icode.nit:275 */
    goto label44;
    label44: while(0);
    stack_frame_head = fra.me.prev;
@@ -2050,33 +2099,35 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    static val_t once_value_11; /* Once value */
    static val_t once_value_12; /* Once value */
    static val_t once_value_13; /* Once value */
-      static val_t once_value_14; /* Once value */
+  static val_t once_value_14; /* Once value */
        static val_t once_value_15; /* Once value */
-      static val_t once_value_17; /* Once value */
+      static val_t once_value_16; /* Once value */
        static val_t once_value_18; /* Once value */
-    static val_t once_value_20; /* Once value */
+      static val_t once_value_19; /* Once value */
      static val_t once_value_21; /* Once value */
      static val_t once_value_22; /* Once value */
      static val_t once_value_23; /* Once value */
-        static val_t once_value_26; /* Once value */
+    static val_t once_value_24; /* Once value */
          static val_t once_value_27; /* Once value */
-        static val_t once_value_29; /* Once value */
+        static val_t once_value_28; /* Once value */
          static val_t once_value_30; /* Once value */
-            static val_t once_value_31; /* Once value */
-        static val_t once_value_33; /* Once value */
-          static val_t once_value_34; /* Once value */
-        static val_t once_value_35; /* Once value */
+        static val_t once_value_31; /* Once value */
+            static val_t once_value_32; /* Once value */
+        static val_t once_value_34; /* Once value */
+          static val_t once_value_35; /* Once value */
          static val_t once_value_36; /* Once value */
          static val_t once_value_37; /* Once value */
          static val_t once_value_38; /* Once value */
-  static val_t once_value_40; /* Once value */
+        static val_t once_value_39; /* Once value */
    static val_t once_value_41; /* Once value */
+  static val_t once_value_42; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 277;
+  fra.me.line = 278;
    fra.me.meth = LOCATE_compiling___compiling_icode___IRoutine___compile_inside_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 10;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -2090,9 +2141,9 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
    fra.me.REG[2] = p2;
-  /* ./compiling//compiling_icode.nit:281 */
+  /* compiling/compiling_icode.nit:282 */
    REGB0 = TAG_Int(0);
-  /* ./compiling//compiling_icode.nit:282 */
+  /* compiling/compiling_icode.nit:283 */
    fra.me.REG[3] = CALL_icode___icode_base___IRoutine___location(fra.me.REG[0])(fra.me.REG[0]);
    REGB1 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
    if (UNTAG_Bool(REGB1)) {
@@ -2108,23 +2159,28 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    }
    REGB1 = TAG_Bool(!UNTAG_Bool(REGB1));
    if (UNTAG_Bool(REGB1)) {
-    /* ./compiling//compiling_icode.nit:283 */
+    /* compiling/compiling_icode.nit:284 */
      fra.me.REG[3] = CALL_icode___icode_base___IRoutine___location(fra.me.REG[0])(fra.me.REG[0]);
      REGB1 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 283);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 284);
      }
      REGB1 = CALL_location___Location___line_start(fra.me.REG[3])(fra.me.REG[3]);
      REGB0 = REGB1;
    }
-  /* ./compiling//compiling_icode.nit:286 */
+  /* compiling/compiling_icode.nit:287 */
    REGB1 = CALL_analysis___allocate_iregister_slots___IRoutine___std_slots_nb(fra.me.REG[0])(fra.me.REG[0]);
    REGB2 = TAG_Int(1);
-  /* ./../lib/standard//kernel.nit:217 */
+  REGB3 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+  if (UNTAG_Bool(REGB3)) {
+  } else {
+    nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+  }
+  /* ../lib/standard/kernel.nit:234 */
    REGB2 = TAG_Bool(UNTAG_Int(REGB1)>UNTAG_Int(REGB2));
-  /* ./compiling//compiling_icode.nit:286 */
+  /* compiling/compiling_icode.nit:287 */
    if (UNTAG_Bool(REGB2)) {
-    /* ./compiling//compiling_icode.nit:287 */
+    /* compiling/compiling_icode.nit:288 */
      REGB2 = TAG_Int(3);
      fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB2);
      if (!once_value_1) {
@@ -2138,9 +2194,9 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
      REGB2 = CALL_analysis___allocate_iregister_slots___IRoutine___std_slots_nb(fra.me.REG[0])(fra.me.REG[0]);
      REGB1 = TAG_Int(1);
-    /* ./../lib/standard//kernel.nit:220 */
+    /* ../lib/standard/kernel.nit:237 */
      REGB1 = TAG_Int(UNTAG_Int(REGB2)-UNTAG_Int(REGB1));
-    /* ./compiling//compiling_icode.nit:287 */
+    /* compiling/compiling_icode.nit:288 */
      fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB1)(REGB1);
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
      if (!once_value_2) {
@@ -2155,7 +2211,7 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
      fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
    } else {
-    /* ./compiling//compiling_icode.nit:289 */
+    /* compiling/compiling_icode.nit:290 */
      if (!once_value_3) {
        fra.me.REG[3] = BOX_NativeString("struct {struct stack_frame_t me;} fra;");
        REGB1 = TAG_Int(38);
@@ -2166,7 +2222,7 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
      fra.me.REG[3] = fra.me.REG[3];
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
    }
-  /* ./compiling//compiling_icode.nit:291 */
+  /* compiling/compiling_icode.nit:292 */
    if (!once_value_4) {
      fra.me.REG[3] = BOX_NativeString("fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;");
      REGB1 = TAG_Int(59);
@@ -2176,7 +2232,7 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    } else fra.me.REG[3] = once_value_4;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:292 */
+  /* compiling/compiling_icode.nit:293 */
    REGB1 = TAG_Int(3);
    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
    if (!once_value_5) {
@@ -2203,7 +2259,7 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:293 */
+  /* compiling/compiling_icode.nit:294 */
    REGB1 = TAG_Int(3);
    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
    if (!once_value_7) {
@@ -2228,7 +2284,7 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:294 */
+  /* compiling/compiling_icode.nit:295 */
    REGB0 = TAG_Int(3);
    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    if (!once_value_9) {
@@ -2253,7 +2309,7 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:295 */
+  /* compiling/compiling_icode.nit:296 */
    if (!once_value_11) {
      fra.me.REG[3] = BOX_NativeString("fra.me.has_broke = 0;");
      REGB0 = TAG_Int(21);
@@ -2263,7 +2319,7 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    } else fra.me.REG[3] = once_value_11;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:296 */
+  /* compiling/compiling_icode.nit:297 */
    REGB0 = TAG_Int(3);
    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    if (!once_value_12) {
@@ -2289,105 +2345,125 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:299 */
+  /* compiling/compiling_icode.nit:298 */
+  if (!once_value_14) {
+    fra.me.REG[3] = BOX_NativeString("fra.me.nitni_local_ref_head = NULL;");
+    REGB0 = TAG_Int(35);
+    fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+    once_value_14 = fra.me.REG[3];
+    register_static_object(&once_value_14);
+  } else fra.me.REG[3] = once_value_14;
+  fra.me.REG[3] = fra.me.REG[3];
+  CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:301 */
    REGB0 = TAG_Int(0);
    REGB1 = CALL_analysis___allocate_iregister_slots___IRoutine___std_slots_nb(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./../lib/standard//kernel.nit:335 */
+  /* ../lib/standard/kernel.nit:352 */
    while(1) {
-    /* ./../lib/standard//kernel.nit:215 */
+    REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+    if (UNTAG_Bool(REGB2)) {
+    } else {
+      nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+    }
+    /* ../lib/standard/kernel.nit:232 */
      REGB2 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
-    /* ./../lib/standard//kernel.nit:335 */
+    /* ../lib/standard/kernel.nit:352 */
      if (UNTAG_Bool(REGB2)) {
-      /* ./compiling//compiling_icode.nit:299 */
+      /* compiling/compiling_icode.nit:301 */
        REGB2 = REGB0;
-      /* ./compiling//compiling_icode.nit:300 */
+      /* compiling/compiling_icode.nit:302 */
        REGB3 = TAG_Int(3);
        fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB3);
-      if (!once_value_14) {
+      if (!once_value_15) {
          fra.me.REG[4] = BOX_NativeString("fra.me.REG[");
          REGB3 = TAG_Int(11);
          fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB3);
-        once_value_14 = fra.me.REG[4];
-        register_static_object(&once_value_14);
-      } else fra.me.REG[4] = once_value_14;
+        once_value_15 = fra.me.REG[4];
+        register_static_object(&once_value_15);
+      } else fra.me.REG[4] = once_value_15;
        fra.me.REG[4] = fra.me.REG[4];
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
        fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB2)(REGB2);
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
-      if (!once_value_15) {
+      if (!once_value_16) {
          fra.me.REG[4] = BOX_NativeString("] = NIT_NULL;");
          REGB2 = TAG_Int(13);
          fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB2);
-        once_value_15 = fra.me.REG[4];
-        register_static_object(&once_value_15);
-      } else fra.me.REG[4] = once_value_15;
+        once_value_16 = fra.me.REG[4];
+        register_static_object(&once_value_16);
+      } else fra.me.REG[4] = once_value_16;
        fra.me.REG[4] = fra.me.REG[4];
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
        fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
        CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-      /* ./../lib/standard//kernel.nit:337 */
+      /* ../lib/standard/kernel.nit:354 */
        REGB2 = TAG_Int(1);
-      /* ./../lib/standard//kernel.nit:218 */
+      /* ../lib/standard/kernel.nit:235 */
        REGB2 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB2));
-      /* ./../lib/standard//kernel.nit:337 */
+      /* ../lib/standard/kernel.nit:354 */
        REGB0 = REGB2;
      } else {
-      /* ./../lib/standard//kernel.nit:335 */
-      goto label16;
+      /* ../lib/standard/kernel.nit:352 */
+      goto label17;
      }
    }
-  label16: while(0);
-  /* ./compiling//compiling_icode.nit:302 */
+  label17: while(0);
+  /* compiling/compiling_icode.nit:304 */
    REGB0 = TAG_Int(0);
    REGB1 = CALL_analysis___allocate_iregister_slots___IRoutine___tag_slots_nb(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./../lib/standard//kernel.nit:335 */
+  /* ../lib/standard/kernel.nit:352 */
    while(1) {
-    /* ./../lib/standard//kernel.nit:215 */
+    REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+    if (UNTAG_Bool(REGB2)) {
+    } else {
+      nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+    }
+    /* ../lib/standard/kernel.nit:232 */
      REGB2 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
-    /* ./../lib/standard//kernel.nit:335 */
+    /* ../lib/standard/kernel.nit:352 */
      if (UNTAG_Bool(REGB2)) {
-      /* ./compiling//compiling_icode.nit:302 */
+      /* compiling/compiling_icode.nit:304 */
        REGB2 = REGB0;
-      /* ./compiling//compiling_icode.nit:303 */
+      /* compiling/compiling_icode.nit:305 */
        REGB3 = TAG_Int(3);
        fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB3);
-      if (!once_value_17) {
+      if (!once_value_18) {
          fra.me.REG[4] = BOX_NativeString("val_t REGB");
          REGB3 = TAG_Int(10);
          fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB3);
-        once_value_17 = fra.me.REG[4];
-        register_static_object(&once_value_17);
-      } else fra.me.REG[4] = once_value_17;
+        once_value_18 = fra.me.REG[4];
+        register_static_object(&once_value_18);
+      } else fra.me.REG[4] = once_value_18;
        fra.me.REG[4] = fra.me.REG[4];
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
        fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB2)(REGB2);
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
-      if (!once_value_18) {
+      if (!once_value_19) {
          fra.me.REG[4] = BOX_NativeString(";");
          REGB2 = TAG_Int(1);
          fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB2);
-        once_value_18 = fra.me.REG[4];
-        register_static_object(&once_value_18);
-      } else fra.me.REG[4] = once_value_18;
+        once_value_19 = fra.me.REG[4];
+        register_static_object(&once_value_19);
+      } else fra.me.REG[4] = once_value_19;
        fra.me.REG[4] = fra.me.REG[4];
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
        fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
        CALL_compiling___compiling_icode___I2CCompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-      /* ./../lib/standard//kernel.nit:337 */
+      /* ../lib/standard/kernel.nit:354 */
        REGB2 = TAG_Int(1);
-      /* ./../lib/standard//kernel.nit:218 */
+      /* ../lib/standard/kernel.nit:235 */
        REGB2 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB2));
-      /* ./../lib/standard//kernel.nit:337 */
+      /* ../lib/standard/kernel.nit:354 */
        REGB0 = REGB2;
      } else {
-      /* ./../lib/standard//kernel.nit:335 */
-      goto label19;
+      /* ../lib/standard/kernel.nit:352 */
+      goto label20;
      }
    }
-  label19: while(0);
-  /* ./compiling//compiling_icode.nit:305 */
+  label20: while(0);
+  /* compiling/compiling_icode.nit:307 */
    fra.me.REG[3] = CALL_icode___icode_base___IRoutine___closure_decls(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:306 */
+  /* compiling/compiling_icode.nit:308 */
    REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -2402,64 +2478,64 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    }
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:307 */
+    /* compiling/compiling_icode.nit:309 */
      REGB0 = TAG_Int(3);
      fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
-    if (!once_value_20) {
+    if (!once_value_21) {
        fra.me.REG[5] = BOX_NativeString("fun_t CREG[");
        REGB0 = TAG_Int(11);
        fra.me.REG[5] = NEW_String_standard___string___String___with_native(fra.me.REG[5], REGB0);
-      once_value_20 = fra.me.REG[5];
-      register_static_object(&once_value_20);
-    } else fra.me.REG[5] = once_value_20;
+      once_value_21 = fra.me.REG[5];
+      register_static_object(&once_value_21);
+    } else fra.me.REG[5] = once_value_21;
      fra.me.REG[5] = fra.me.REG[5];
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
      REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 307);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 309);
      }
      REGB0 = CALL_standard___collection___abstract_collection___Collection___length(fra.me.REG[3])(fra.me.REG[3]);
      fra.me.REG[5] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
-    if (!once_value_21) {
+    if (!once_value_22) {
        fra.me.REG[5] = BOX_NativeString("];");
        REGB0 = TAG_Int(2);
        fra.me.REG[5] = NEW_String_standard___string___String___with_native(fra.me.REG[5], REGB0);
-      once_value_21 = fra.me.REG[5];
-      register_static_object(&once_value_21);
-    } else fra.me.REG[5] = once_value_21;
+      once_value_22 = fra.me.REG[5];
+      register_static_object(&once_value_22);
+    } else fra.me.REG[5] = once_value_22;
      fra.me.REG[5] = fra.me.REG[5];
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
      fra.me.REG[4] = CALL_standard___string___Object___to_s(fra.me.REG[4])(fra.me.REG[4]);
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-    /* ./compiling//compiling_icode.nit:308 */
-    if (!once_value_22) {
+    /* compiling/compiling_icode.nit:310 */
+    if (!once_value_23) {
        fra.me.REG[4] = BOX_NativeString("fra.me.closure_ctx = closctx_param;");
        REGB0 = TAG_Int(35);
        fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
-      once_value_22 = fra.me.REG[4];
-      register_static_object(&once_value_22);
-    } else fra.me.REG[4] = once_value_22;
+      once_value_23 = fra.me.REG[4];
+      register_static_object(&once_value_23);
+    } else fra.me.REG[4] = once_value_23;
      fra.me.REG[4] = fra.me.REG[4];
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-    /* ./compiling//compiling_icode.nit:309 */
-    if (!once_value_23) {
+    /* compiling/compiling_icode.nit:311 */
+    if (!once_value_24) {
        fra.me.REG[4] = BOX_NativeString("fra.me.closure_funs = CREG;");
        REGB0 = TAG_Int(27);
        fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
-      once_value_23 = fra.me.REG[4];
-      register_static_object(&once_value_23);
-    } else fra.me.REG[4] = once_value_23;
+      once_value_24 = fra.me.REG[4];
+      register_static_object(&once_value_24);
+    } else fra.me.REG[4] = once_value_24;
      fra.me.REG[4] = fra.me.REG[4];
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
    }
-  /* ./compiling//compiling_icode.nit:311 */
+  /* compiling/compiling_icode.nit:313 */
    REGB0 = TAG_Int(0);
    fra.me.REG[4] = REGB0;
-  /* ./compiling//compiling_icode.nit:312 */
+  /* compiling/compiling_icode.nit:314 */
    fra.me.REG[5] = CALL_icode___icode_base___IRoutine___params(fra.me.REG[0])(fra.me.REG[0]);
-  CALL_standard___collection___abstract_collection___Collection___iterate(fra.me.REG[5])(fra.me.REG[5], (&(fra.me)), ((fun_t)OC_compiling___compiling_icode___IRoutine___compile_inside_to_c_24));
-  /* ./compiling//compiling_icode.nit:316 */
+  CALL_standard___collection___abstract_collection___Collection___iterate(fra.me.REG[5])(fra.me.REG[5], (&(fra.me)), ((fun_t)OC_compiling___compiling_icode___IRoutine___compile_inside_to_c_25));
+  /* compiling/compiling_icode.nit:318 */
    REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -2474,164 +2550,184 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    }
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:317 */
+    /* compiling/compiling_icode.nit:319 */
      REGB0 = TAG_Int(0);
      REGB1 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 317);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 319);
      }
      REGB1 = CALL_standard___collection___abstract_collection___Collection___length(fra.me.REG[3])(fra.me.REG[3]);
-    /* ./../lib/standard//kernel.nit:335 */
+    /* ../lib/standard/kernel.nit:352 */
      while(1) {
-      /* ./../lib/standard//kernel.nit:215 */
+      REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+      if (UNTAG_Bool(REGB2)) {
+      } else {
+        nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+      }
+      /* ../lib/standard/kernel.nit:232 */
        REGB2 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
-      /* ./../lib/standard//kernel.nit:335 */
+      /* ../lib/standard/kernel.nit:352 */
        if (UNTAG_Bool(REGB2)) {
-        /* ./compiling//compiling_icode.nit:317 */
+        /* compiling/compiling_icode.nit:319 */
          REGB2 = REGB0;
-        /* ./compiling//compiling_icode.nit:318 */
+        /* compiling/compiling_icode.nit:320 */
          REGB3 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
          if (UNTAG_Bool(REGB3)) {
-          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 318);
+          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 320);
          }
-        fra.me.REG[4] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[3])(fra.me.REG[3], REGB2);
-        /* ./compiling//compiling_icode.nit:319 */
+        fra.me.REG[4] = CALL_standard___collection___abstract_collection___SequenceRead_____bra(fra.me.REG[3])(fra.me.REG[3], REGB2);
+        /* compiling/compiling_icode.nit:321 */
          REGB3 = TAG_Int(5);
          fra.me.REG[5] = NEW_Array_standard___collection___array___Array___with_capacity(REGB3);
-        if (!once_value_26) {
+        if (!once_value_27) {
            fra.me.REG[6] = BOX_NativeString("CREG[");
            REGB3 = TAG_Int(5);
            fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB3);
-          once_value_26 = fra.me.REG[6];
-          register_static_object(&once_value_26);
-        } else fra.me.REG[6] = once_value_26;
+          once_value_27 = fra.me.REG[6];
+          register_static_object(&once_value_27);
+        } else fra.me.REG[6] = once_value_27;
          fra.me.REG[6] = fra.me.REG[6];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[6]);
          fra.me.REG[6] = CALL_standard___string___Object___to_s(REGB2)(REGB2);
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[6]);
-        if (!once_value_27) {
+        if (!once_value_28) {
            fra.me.REG[6] = BOX_NativeString("] = ");
            REGB3 = TAG_Int(4);
            fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB3);
-          once_value_27 = fra.me.REG[6];
-          register_static_object(&once_value_27);
-        } else fra.me.REG[6] = once_value_27;
+          once_value_28 = fra.me.REG[6];
+          register_static_object(&once_value_28);
+        } else fra.me.REG[6] = once_value_28;
          fra.me.REG[6] = fra.me.REG[6];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[6]);
          fra.me.REG[6] = CALL_icode___icode_base___IRoutine___params(fra.me.REG[0])(fra.me.REG[0]);
          REGB3 = CALL_standard___collection___abstract_collection___Collection___length(fra.me.REG[6])(fra.me.REG[6]);
-        /* ./../lib/standard//kernel.nit:218 */
+        /* ../lib/standard/kernel.nit:235 */
          REGB3 = TAG_Int(UNTAG_Int(REGB3)+UNTAG_Int(REGB2));
-        /* ./../lib/standard//collection//array.nit:243 */
+        /* ../lib/standard/collection/array.nit:278 */
          fra.me.REG[6] = fra.me.REG[2];
-        /* ./../lib/standard//collection//array.nit:245 */
+        /* ../lib/standard/collection/array.nit:280 */
          REGB4 = TAG_Int(0);
-        /* ./../lib/standard//kernel.nit:216 */
+        REGB5 = TAG_Bool(VAL_ISA(REGB4, VTCOLOR_standard___kernel___Comparable___OTHER(REGB3), VTID_standard___kernel___Comparable___OTHER(REGB3))) /*cast OTHER*/;
+        if (UNTAG_Bool(REGB5)) {
+        } else {
+          nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+        }
+        /* ../lib/standard/kernel.nit:233 */
          REGB4 = TAG_Bool(UNTAG_Int(REGB3)>=UNTAG_Int(REGB4));
-        /* ./../lib/standard//collection//array.nit:245 */
+        /* ../lib/standard/collection/array.nit:280 */
          if (UNTAG_Bool(REGB4)) {
            REGB4 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[6])!=NIT_NULL);
            if (UNTAG_Bool(REGB4)) {
            } else {
-            nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+            nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
            }
            REGB4 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[6]);
-          /* ./../lib/standard//kernel.nit:215 */
+          REGB5 = TAG_Bool(VAL_ISA(REGB4, VTCOLOR_standard___kernel___Comparable___OTHER(REGB3), VTID_standard___kernel___Comparable___OTHER(REGB3))) /*cast OTHER*/;
+          if (UNTAG_Bool(REGB5)) {
+          } else {
+            nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+          }
+          /* ../lib/standard/kernel.nit:232 */
            REGB4 = TAG_Bool(UNTAG_Int(REGB3)<UNTAG_Int(REGB4));
          } else {
-          /* ./../lib/standard//collection//array.nit:245 */
+          /* ../lib/standard/collection/array.nit:280 */
            REGB5 = TAG_Bool(false);
            REGB4 = REGB5;
          }
          if (UNTAG_Bool(REGB4)) {
          } else {
-          nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+          nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
          }
-        /* ./../lib/standard//collection//array.nit:246 */
+        /* ../lib/standard/collection/array.nit:281 */
          fra.me.REG[6] = ATTR_standard___collection___array___Array____items(fra.me.REG[6]);
          REGB4 = TAG_Bool(fra.me.REG[6]==NIT_NULL);
          if (UNTAG_Bool(REGB4)) {
-          nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+          nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
          }
-        /* ./../lib/standard//collection//array.nit:654 */
+        /* ../lib/standard/collection/array.nit:718 */
          fra.me.REG[6] = ((Nit_NativeArray)fra.me.REG[6])->val[UNTAG_Int(REGB3)];
-        /* ./../lib/standard//collection//array.nit:246 */
-        goto label28;
-        label28: while(0);
-        /* ./compiling//compiling_icode.nit:319 */
+        /* ../lib/standard/collection/array.nit:281 */
+        goto label29;
+        label29: while(0);
+        /* compiling/compiling_icode.nit:321 */
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[6]);
-        if (!once_value_29) {
+        if (!once_value_30) {
            fra.me.REG[6] = BOX_NativeString(";");
            REGB3 = TAG_Int(1);
            fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB3);
-          once_value_29 = fra.me.REG[6];
-          register_static_object(&once_value_29);
-        } else fra.me.REG[6] = once_value_29;
+          once_value_30 = fra.me.REG[6];
+          register_static_object(&once_value_30);
+        } else fra.me.REG[6] = once_value_30;
          fra.me.REG[6] = fra.me.REG[6];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[6]);
          fra.me.REG[5] = CALL_standard___string___Object___to_s(fra.me.REG[5])(fra.me.REG[5]);
          CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
-        /* ./compiling//compiling_icode.nit:320 */
+        /* compiling/compiling_icode.nit:322 */
          fra.me.REG[5] = CALL_compiling___compiling_icode___I2CCompilerVisitor___closures(fra.me.REG[1])(fra.me.REG[1]);
          fra.me.REG[6] = CALL_standard___string___Object___to_s(REGB2)(REGB2);
          CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[4], fra.me.REG[6]);
-        /* ./compiling//compiling_icode.nit:321 */
+        /* compiling/compiling_icode.nit:323 */
          fra.me.REG[6] = CALL_icode___icode_base___IClosureDecl___closure(fra.me.REG[4])(fra.me.REG[4]);
          fra.me.REG[6] = CALL_metamodel___static_type___MMClosure___signature(fra.me.REG[6])(fra.me.REG[6]);
-        /* ./compiling//compiling_icode.nit:322 */
+        /* compiling/compiling_icode.nit:324 */
          fra.me.REG[5] = NEW_Array_standard___collection___array___Array___init();
-        /* ./compiling//compiling_icode.nit:323 */
-        if (!once_value_30) {
+        /* compiling/compiling_icode.nit:325 */
+        if (!once_value_31) {
            fra.me.REG[7] = BOX_NativeString("struct stack_frame_t *");
            REGB2 = TAG_Int(22);
            fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB2);
-          once_value_30 = fra.me.REG[7];
-          register_static_object(&once_value_30);
-        } else fra.me.REG[7] = once_value_30;
+          once_value_31 = fra.me.REG[7];
+          register_static_object(&once_value_31);
+        } else fra.me.REG[7] = once_value_31;
          fra.me.REG[7] = fra.me.REG[7];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[7]);
-        /* ./compiling//compiling_icode.nit:324 */
+        /* compiling/compiling_icode.nit:326 */
          REGB2 = TAG_Int(0);
          REGB3 = CALL_metamodel___static_type___MMSignature___arity(fra.me.REG[6])(fra.me.REG[6]);
-        /* ./../lib/standard//kernel.nit:335 */
+        /* ../lib/standard/kernel.nit:352 */
          while(1) {
-          /* ./../lib/standard//kernel.nit:215 */
+          REGB4 = TAG_Bool(VAL_ISA(REGB3, VTCOLOR_standard___kernel___Comparable___OTHER(REGB2), VTID_standard___kernel___Comparable___OTHER(REGB2))) /*cast OTHER*/;
+          if (UNTAG_Bool(REGB4)) {
+          } else {
+            nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+          }
+          /* ../lib/standard/kernel.nit:232 */
            REGB4 = TAG_Bool(UNTAG_Int(REGB2)<UNTAG_Int(REGB3));
-          /* ./../lib/standard//kernel.nit:335 */
+          /* ../lib/standard/kernel.nit:352 */
            if (UNTAG_Bool(REGB4)) {
-            /* ./compiling//compiling_icode.nit:325 */
-            if (!once_value_31) {
+            /* compiling/compiling_icode.nit:327 */
+            if (!once_value_32) {
                fra.me.REG[7] = BOX_NativeString("val_t");
                REGB4 = TAG_Int(5);
                fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB4);
-              once_value_31 = fra.me.REG[7];
-              register_static_object(&once_value_31);
-            } else fra.me.REG[7] = once_value_31;
+              once_value_32 = fra.me.REG[7];
+              register_static_object(&once_value_32);
+            } else fra.me.REG[7] = once_value_32;
              fra.me.REG[7] = fra.me.REG[7];
-            /* ./compiling//compiling_icode.nit:326 */
+            /* compiling/compiling_icode.nit:328 */
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[7]);
-            /* ./../lib/standard//kernel.nit:337 */
+            /* ../lib/standard/kernel.nit:354 */
              REGB4 = TAG_Int(1);
-            /* ./../lib/standard//kernel.nit:218 */
+            /* ../lib/standard/kernel.nit:235 */
              REGB4 = TAG_Int(UNTAG_Int(REGB2)+UNTAG_Int(REGB4));
-            /* ./../lib/standard//kernel.nit:337 */
+            /* ../lib/standard/kernel.nit:354 */
              REGB2 = REGB4;
            } else {
-            /* ./../lib/standard//kernel.nit:335 */
-            goto label32;
+            /* ../lib/standard/kernel.nit:352 */
+            goto label33;
            }
          }
-        label32: while(0);
-        /* ./compiling//compiling_icode.nit:328 */
-        if (!once_value_33) {
+        label33: while(0);
+        /* compiling/compiling_icode.nit:330 */
+        if (!once_value_34) {
            fra.me.REG[7] = BOX_NativeString("void");
            REGB2 = TAG_Int(4);
            fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB2);
-          once_value_33 = fra.me.REG[7];
-          register_static_object(&once_value_33);
-        } else fra.me.REG[7] = once_value_33;
+          once_value_34 = fra.me.REG[7];
+          register_static_object(&once_value_34);
+        } else fra.me.REG[7] = once_value_34;
          fra.me.REG[7] = fra.me.REG[7];
-        /* ./compiling//compiling_icode.nit:329 */
+        /* compiling/compiling_icode.nit:331 */
          fra.me.REG[6] = CALL_metamodel___static_type___MMSignature___return_type(fra.me.REG[6])(fra.me.REG[6]);
          REGB2 = TAG_Bool(fra.me.REG[6]==NIT_NULL);
          if (UNTAG_Bool(REGB2)) {
@@ -2647,106 +2743,106 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
          }
          REGB2 = TAG_Bool(!UNTAG_Bool(REGB2));
          if (UNTAG_Bool(REGB2)) {
-          if (!once_value_34) {
+          if (!once_value_35) {
              fra.me.REG[6] = BOX_NativeString("val_t");
              REGB2 = TAG_Int(5);
              fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB2);
-            once_value_34 = fra.me.REG[6];
-            register_static_object(&once_value_34);
-          } else fra.me.REG[6] = once_value_34;
+            once_value_35 = fra.me.REG[6];
+            register_static_object(&once_value_35);
+          } else fra.me.REG[6] = once_value_35;
            fra.me.REG[6] = fra.me.REG[6];
            fra.me.REG[7] = fra.me.REG[6];
          }
-        /* ./compiling//compiling_icode.nit:330 */
+        /* compiling/compiling_icode.nit:332 */
          fra.me.REG[6] = CALL_compiling___compiling_icode___I2CCompilerVisitor___clostypes(fra.me.REG[1])(fra.me.REG[1]);
          REGB2 = TAG_Int(5);
          fra.me.REG[8] = NEW_Array_standard___collection___array___Array___with_capacity(REGB2);
-        if (!once_value_35) {
+        if (!once_value_36) {
            fra.me.REG[9] = BOX_NativeString("");
            REGB2 = TAG_Int(0);
            fra.me.REG[9] = NEW_String_standard___string___String___with_native(fra.me.REG[9], REGB2);
-          once_value_35 = fra.me.REG[9];
-          register_static_object(&once_value_35);
-        } else fra.me.REG[9] = once_value_35;
+          once_value_36 = fra.me.REG[9];
+          register_static_object(&once_value_36);
+        } else fra.me.REG[9] = once_value_36;
          fra.me.REG[9] = fra.me.REG[9];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[9]);
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[7]);
-        if (!once_value_36) {
+        if (!once_value_37) {
            fra.me.REG[7] = BOX_NativeString(" (*)(");
            REGB2 = TAG_Int(5);
            fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB2);
-          once_value_36 = fra.me.REG[7];
-          register_static_object(&once_value_36);
-        } else fra.me.REG[7] = once_value_36;
+          once_value_37 = fra.me.REG[7];
+          register_static_object(&once_value_37);
+        } else fra.me.REG[7] = once_value_37;
          fra.me.REG[7] = fra.me.REG[7];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[7]);
-        if (!once_value_37) {
+        if (!once_value_38) {
            fra.me.REG[7] = BOX_NativeString(", ");
            REGB2 = TAG_Int(2);
            fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB2);
-          once_value_37 = fra.me.REG[7];
-          register_static_object(&once_value_37);
-        } else fra.me.REG[7] = once_value_37;
+          once_value_38 = fra.me.REG[7];
+          register_static_object(&once_value_38);
+        } else fra.me.REG[7] = once_value_38;
          fra.me.REG[7] = fra.me.REG[7];
          fra.me.REG[7] = CALL_standard___string___Collection___join(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[7]);
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[7]);
-        if (!once_value_38) {
+        if (!once_value_39) {
            fra.me.REG[7] = BOX_NativeString(")");
            REGB2 = TAG_Int(1);
            fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB2);
-          once_value_38 = fra.me.REG[7];
-          register_static_object(&once_value_38);
-        } else fra.me.REG[7] = once_value_38;
+          once_value_39 = fra.me.REG[7];
+          register_static_object(&once_value_39);
+        } else fra.me.REG[7] = once_value_39;
          fra.me.REG[7] = fra.me.REG[7];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[7]);
          fra.me.REG[8] = CALL_standard___string___Object___to_s(fra.me.REG[8])(fra.me.REG[8]);
          CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[4], fra.me.REG[8]);
-        /* ./../lib/standard//kernel.nit:337 */
+        /* ../lib/standard/kernel.nit:354 */
          REGB2 = TAG_Int(1);
-        /* ./../lib/standard//kernel.nit:218 */
+        /* ../lib/standard/kernel.nit:235 */
          REGB2 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB2));
-        /* ./../lib/standard//kernel.nit:337 */
+        /* ../lib/standard/kernel.nit:354 */
          REGB0 = REGB2;
        } else {
-        /* ./../lib/standard//kernel.nit:335 */
-        goto label39;
+        /* ../lib/standard/kernel.nit:352 */
+        goto label40;
        }
      }
-    label39: while(0);
+    label40: while(0);
    }
-  /* ./compiling//compiling_icode.nit:333 */
-  if (!once_value_40) {
+  /* compiling/compiling_icode.nit:335 */
+  if (!once_value_41) {
      fra.me.REG[2] = BOX_NativeString("val_t tmp;");
      REGB0 = TAG_Int(10);
      fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
-    once_value_40 = fra.me.REG[2];
-    register_static_object(&once_value_40);
-  } else fra.me.REG[2] = once_value_40;
+    once_value_41 = fra.me.REG[2];
+    register_static_object(&once_value_41);
+  } else fra.me.REG[2] = once_value_41;
    fra.me.REG[2] = fra.me.REG[2];
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:336 */
+  /* compiling/compiling_icode.nit:338 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___return_label(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:337 */
+  /* compiling/compiling_icode.nit:339 */
    fra.me.REG[3] = CALL_icode___icode_base___IRoutine___body(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___return_label__eq(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:340 */
+  /* compiling/compiling_icode.nit:342 */
    fra.me.REG[3] = CALL_icode___icode_base___IRoutine___body(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___ICode___compile_to_c(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:342 */
-  if (!once_value_41) {
+  /* compiling/compiling_icode.nit:344 */
+  if (!once_value_42) {
      fra.me.REG[3] = BOX_NativeString("stack_frame_head = fra.me.prev;");
      REGB0 = TAG_Int(31);
      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-    once_value_41 = fra.me.REG[3];
-    register_static_object(&once_value_41);
-  } else fra.me.REG[3] = once_value_41;
+    once_value_42 = fra.me.REG[3];
+    register_static_object(&once_value_42);
+  } else fra.me.REG[3] = once_value_42;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:343 */
+  /* compiling/compiling_icode.nit:345 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___return_label__eq(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:344 */
+  /* compiling/compiling_icode.nit:346 */
    fra.me.REG[0] = CALL_icode___icode_base___IRoutine___result(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:345 */
+  /* compiling/compiling_icode.nit:347 */
    REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -2761,19 +2857,19 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
    }
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:346 */
+    /* compiling/compiling_icode.nit:348 */
      fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-    goto label42;
+    goto label43;
    } else {
-    /* ./compiling//compiling_icode.nit:348 */
+    /* compiling/compiling_icode.nit:350 */
      fra.me.REG[0] = NIT_NULL;
-    goto label42;
+    goto label43;
    }
-  label42: while(0);
+  label43: while(0);
    stack_frame_head = fra.me.prev;
    return fra.me.REG[0];
  }
-  void OC_compiling___compiling_icode___IRoutine___compile_inside_to_c_24(struct stack_frame_t *closctx, val_t p0, struct stack_frame_t *closctx_param, fun_t clos_fun0){
+  void OC_compiling___compiling_icode___IRoutine___compile_inside_to_c_25(struct stack_frame_t *closctx, val_t p0, struct stack_frame_t *closctx_param, fun_t clos_fun0){
      struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
      val_t REGB0;
      val_t REGB1;
@@ -2786,13 +2882,14 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
      fra.me.meth = LOCATE_compiling___compiling_icode___IRoutine___compile_inside_to_c;
      fra.me.has_broke = 0;
      fra.me.REG_size = 2;
+    fra.me.nitni_local_ref_head = NULL;
      fra.me.REG[0] = NIT_NULL;
      fra.me.REG[1] = NIT_NULL;
      fra.me.closure_ctx = closctx_param;
      fra.me.closure_funs = CREG;
      fra.me.REG[0] = p0;
      CREG[0] = clos_fun0;
-    /* ./compiling//compiling_icode.nit:313 */
+    /* compiling/compiling_icode.nit:315 */
      fra.me.REG[1] = CALL_analysis___allocate_iregister_slots___IRegister___slot_index(fra.me.REG[0])(fra.me.REG[0]);
      REGB0 = TAG_Bool(fra.me.REG[1]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
@@ -2802,60 +2899,70 @@ val_t compiling___compiling_icode___IRoutine___compile_inside_to_c(val_t p0, val
          REGB1 = TAG_Bool(false);
          REGB0 = REGB1;
        } else {
-        /* ./../lib/standard//kernel.nit:210 */
+        /* ../lib/standard/kernel.nit:227 */
          REGB1 = TAG_Bool((fra.me.REG[1])==(NIT_NULL));
-        /* ./compiling//compiling_icode.nit:313 */
+        /* compiling/compiling_icode.nit:315 */
          REGB0 = REGB1;
        }
      }
      REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
      if (UNTAG_Bool(REGB0)) {
        fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(closctx->REG[1])(closctx->REG[1], fra.me.REG[0]);
-      /* ./../lib/standard//collection//array.nit:243 */
+      /* ../lib/standard/collection/array.nit:278 */
        fra.me.REG[1] = closctx->REG[2];
        REGB0 = closctx->REG[4];
-      /* ./../lib/standard//collection//array.nit:245 */
+      /* ../lib/standard/collection/array.nit:280 */
        REGB1 = TAG_Int(0);
-      /* ./../lib/standard//kernel.nit:216 */
+      REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+      if (UNTAG_Bool(REGB2)) {
+      } else {
+        nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+      }
+      /* ../lib/standard/kernel.nit:233 */
        REGB1 = TAG_Bool(UNTAG_Int(REGB0)>=UNTAG_Int(REGB1));
-      /* ./../lib/standard//collection//array.nit:245 */
+      /* ../lib/standard/collection/array.nit:280 */
        if (UNTAG_Bool(REGB1)) {
          REGB1 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1])!=NIT_NULL);
          if (UNTAG_Bool(REGB1)) {
          } else {
-          nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+          nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
          }
          REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1]);
-        /* ./../lib/standard//kernel.nit:215 */
+        REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+        if (UNTAG_Bool(REGB2)) {
+        } else {
+          nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+        }
+        /* ../lib/standard/kernel.nit:232 */
          REGB1 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
        } else {
-        /* ./../lib/standard//collection//array.nit:245 */
+        /* ../lib/standard/collection/array.nit:280 */
          REGB2 = TAG_Bool(false);
          REGB1 = REGB2;
        }
        if (UNTAG_Bool(REGB1)) {
        } else {
-        nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+        nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
        }
-      /* ./../lib/standard//collection//array.nit:246 */
+      /* ../lib/standard/collection/array.nit:281 */
        fra.me.REG[1] = ATTR_standard___collection___array___Array____items(fra.me.REG[1]);
        REGB1 = TAG_Bool(fra.me.REG[1]==NIT_NULL);
        if (UNTAG_Bool(REGB1)) {
-        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
        }
-      /* ./../lib/standard//collection//array.nit:654 */
+      /* ../lib/standard/collection/array.nit:718 */
        fra.me.REG[1] = ((Nit_NativeArray)fra.me.REG[1])->val[UNTAG_Int(REGB0)];
-      /* ./../lib/standard//collection//array.nit:246 */
-      goto label25;
-      label25: while(0);
-      /* ./compiling//compiling_icode.nit:313 */
+      /* ../lib/standard/collection/array.nit:281 */
+      goto label26;
+      label26: while(0);
+      /* compiling/compiling_icode.nit:315 */
        CALL_compiling___compiling_icode___I2CCompilerVisitor___add_assignment(closctx->REG[1])(closctx->REG[1], fra.me.REG[0], fra.me.REG[1]);
      }
-    /* ./compiling//compiling_icode.nit:314 */
+    /* compiling/compiling_icode.nit:316 */
      REGB0 = TAG_Int(1);
-    /* ./../lib/standard//kernel.nit:218 */
+    /* ../lib/standard/kernel.nit:235 */
      REGB0 = TAG_Int(UNTAG_Int(closctx->REG[4])+UNTAG_Int(REGB0));
-    /* ./compiling//compiling_icode.nit:314 */
+    /* compiling/compiling_icode.nit:316 */
      closctx->REG[4] = REGB0;
      stack_frame_head = fra.me.prev;
      return;
@@ -2865,10 +2972,11 @@ val_t compiling___compiling_icode___IRoutine___compile_to_c(val_t p0, val_t p1,
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 352;
+  fra.me.line = 354;
    fra.me.meth = LOCATE_compiling___compiling_icode___IRoutine___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -2877,9 +2985,9 @@ val_t compiling___compiling_icode___IRoutine___compile_to_c(val_t p0, val_t p1,
    fra.me.REG[1] = p1;
    fra.me.REG[2] = p2;
    fra.me.REG[3] = p3;
-  /* ./compiling//compiling_icode.nit:356 */
+  /* compiling/compiling_icode.nit:358 */
    fra.me.REG[2] = NEW_I2CCompilerVisitor_compiling___compiling_icode___I2CCompilerVisitor___init(fra.me.REG[1], fra.me.REG[0], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:357 */
+  /* compiling/compiling_icode.nit:359 */
    fra.me.REG[3] = CALL_compiling___compiling_icode___IRoutine___compile_inside_to_c(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[2], fra.me.REG[3]);
    goto label1;
    label1: while(0);
@@ -2891,12 +2999,13 @@ void compiling___compiling_icode___ICode___compile_to_c(val_t p0, val_t p1){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 362;
+  fra.me.line = 364;
    fra.me.meth = LOCATE_compiling___compiling_icode___ICode___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 0;
-  /* ./compiling//compiling_icode.nit:362 */
-  nit_abort("Deferred method called", NULL, LOCATE_compiling___compiling_icode, 362);
+  fra.me.nitni_local_ref_head = NULL;
+  /* compiling/compiling_icode.nit:364 */
+  nit_abort("Deferred method called", NULL, LOCATE_compiling___compiling_icode, 364);
    stack_frame_head = fra.me.prev;
    return;
  }
@@ -2907,15 +3016,16 @@ val_t compiling___compiling_icode___ICode___need_result(val_t p0){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 365;
+  fra.me.line = 367;
    fra.me.meth = LOCATE_compiling___compiling_icode___ICode___need_result;
    fra.me.has_broke = 0;
    fra.me.REG_size = 1;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[0] = p0;
-  /* ./compiling//compiling_icode.nit:368 */
+  /* compiling/compiling_icode.nit:370 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode___result(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:369 */
+  /* compiling/compiling_icode.nit:371 */
    REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -2932,7 +3042,7 @@ val_t compiling___compiling_icode___ICode___need_result(val_t p0){
    if (UNTAG_Bool(REGB0)) {
      REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 369);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 371);
      }
      fra.me.REG[0] = CALL_analysis___allocate_iregister_slots___IRegister___slot_index(fra.me.REG[0])(fra.me.REG[0]);
      REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
@@ -2943,9 +3053,9 @@ val_t compiling___compiling_icode___ICode___need_result(val_t p0){
          REGB1 = TAG_Bool(false);
          REGB0 = REGB1;
        } else {
-        /* ./../lib/standard//kernel.nit:210 */
+        /* ../lib/standard/kernel.nit:227 */
          REGB1 = TAG_Bool((fra.me.REG[0])==(NIT_NULL));
-        /* ./compiling//compiling_icode.nit:369 */
+        /* compiling/compiling_icode.nit:371 */
          REGB0 = REGB1;
        }
      }
@@ -2969,10 +3079,11 @@ void compiling___compiling_icode___ICode___store_result(val_t p0, val_t p1, val_
        static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 372;
+  fra.me.line = 374;
    fra.me.meth = LOCATE_compiling___compiling_icode___ICode___store_result;
    fra.me.has_broke = 0;
    fra.me.REG_size = 5;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -2981,9 +3092,9 @@ void compiling___compiling_icode___ICode___store_result(val_t p0, val_t p1, val_
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
    fra.me.REG[2] = p2;
-  /* ./compiling//compiling_icode.nit:375 */
+  /* compiling/compiling_icode.nit:377 */
    fra.me.REG[3] = CALL_icode___icode_base___ICode___result(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:376 */
+  /* compiling/compiling_icode.nit:378 */
    REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -3000,7 +3111,7 @@ void compiling___compiling_icode___ICode___store_result(val_t p0, val_t p1, val_
    if (UNTAG_Bool(REGB0)) {
      REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 376);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 378);
      }
      fra.me.REG[4] = CALL_analysis___allocate_iregister_slots___IRegister___slot_index(fra.me.REG[3])(fra.me.REG[3]);
      REGB0 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
@@ -3011,9 +3122,9 @@ void compiling___compiling_icode___ICode___store_result(val_t p0, val_t p1, val_
          REGB1 = TAG_Bool(false);
          REGB0 = REGB1;
        } else {
-        /* ./../lib/standard//kernel.nit:210 */
+        /* ../lib/standard/kernel.nit:227 */
          REGB1 = TAG_Bool((fra.me.REG[4])==(NIT_NULL));
-        /* ./compiling//compiling_icode.nit:376 */
+        /* compiling/compiling_icode.nit:378 */
          REGB0 = REGB1;
        }
      }
@@ -3023,7 +3134,7 @@ void compiling___compiling_icode___ICode___store_result(val_t p0, val_t p1, val_
      REGB0 = REGB1;
    }
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:377 */
+    /* compiling/compiling_icode.nit:379 */
      REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
      } else {
@@ -3039,14 +3150,14 @@ void compiling___compiling_icode___ICode___store_result(val_t p0, val_t p1, val_
      REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
      if (UNTAG_Bool(REGB0)) {
      } else {
-      nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 377);
+      nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 379);
      }
-    /* ./compiling//compiling_icode.nit:378 */
+    /* compiling/compiling_icode.nit:380 */
      fra.me.REG[4] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:379 */
+    /* compiling/compiling_icode.nit:381 */
      fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:380 */
+    /* compiling/compiling_icode.nit:382 */
      if (!once_value_1) {
        fra.me.REG[3] = BOX_NativeString(" = ");
        REGB0 = TAG_Int(3);
@@ -3056,9 +3167,9 @@ void compiling___compiling_icode___ICode___store_result(val_t p0, val_t p1, val_
      } else fra.me.REG[3] = once_value_1;
      fra.me.REG[3] = fra.me.REG[3];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:381 */
+    /* compiling/compiling_icode.nit:383 */
      CALL_compiling___compiling_writer___Writer___append(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[2]);
-    /* ./compiling//compiling_icode.nit:382 */
+    /* compiling/compiling_icode.nit:384 */
      if (!once_value_2) {
        fra.me.REG[3] = BOX_NativeString(";\n");
        REGB0 = TAG_Int(2);
@@ -3069,7 +3180,7 @@ void compiling___compiling_icode___ICode___store_result(val_t p0, val_t p1, val_
      fra.me.REG[3] = fra.me.REG[3];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
    } else {
-    /* ./compiling//compiling_icode.nit:383 */
+    /* compiling/compiling_icode.nit:385 */
      REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
      } else {
@@ -3091,11 +3202,11 @@ void compiling___compiling_icode___ICode___store_result(val_t p0, val_t p1, val_
        REGB0 = REGB1;
      }
      if (UNTAG_Bool(REGB0)) {
-      /* ./compiling//compiling_icode.nit:386 */
+      /* compiling/compiling_icode.nit:388 */
        fra.me.REG[1] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
-      /* ./compiling//compiling_icode.nit:387 */
+      /* compiling/compiling_icode.nit:389 */
        CALL_compiling___compiling_writer___Writer___append(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-      /* ./compiling//compiling_icode.nit:388 */
+      /* compiling/compiling_icode.nit:390 */
        if (!once_value_3) {
          fra.me.REG[2] = BOX_NativeString(";\n");
          REGB0 = TAG_Int(2);
@@ -3119,17 +3230,18 @@ val_t compiling___compiling_icode___ICode___new_result(val_t p0, val_t p1){
    static val_t once_value_2; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 392;
+  fra.me.line = 394;
    fra.me.meth = LOCATE_compiling___compiling_icode___ICode___new_result;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:396 */
+  /* compiling/compiling_icode.nit:398 */
    REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
    if (UNTAG_Bool(REGB0)) {
      REGB0 = TAG_Bool(true);
@@ -3140,13 +3252,13 @@ val_t compiling___compiling_icode___ICode___new_result(val_t p0, val_t p1){
    }
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 396);
+    nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 398);
    }
-  /* ./compiling//compiling_icode.nit:397 */
+  /* compiling/compiling_icode.nit:399 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:398 */
+  /* compiling/compiling_icode.nit:400 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode___result(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:399 */
+  /* compiling/compiling_icode.nit:401 */
    REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -3163,7 +3275,7 @@ val_t compiling___compiling_icode___ICode___new_result(val_t p0, val_t p1){
    if (UNTAG_Bool(REGB0)) {
      REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 399);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 401);
      }
      fra.me.REG[3] = CALL_analysis___allocate_iregister_slots___IRegister___slot_index(fra.me.REG[0])(fra.me.REG[0]);
      REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
@@ -3174,9 +3286,9 @@ val_t compiling___compiling_icode___ICode___new_result(val_t p0, val_t p1){
          REGB1 = TAG_Bool(false);
          REGB0 = REGB1;
        } else {
-        /* ./../lib/standard//kernel.nit:210 */
+        /* ../lib/standard/kernel.nit:227 */
          REGB1 = TAG_Bool((fra.me.REG[3])==(NIT_NULL));
-        /* ./compiling//compiling_icode.nit:399 */
+        /* compiling/compiling_icode.nit:401 */
          REGB0 = REGB1;
        }
      }
@@ -3186,10 +3298,10 @@ val_t compiling___compiling_icode___ICode___new_result(val_t p0, val_t p1){
      REGB0 = REGB1;
    }
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:400 */
+    /* compiling/compiling_icode.nit:402 */
      fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-    /* ./compiling//compiling_icode.nit:401 */
+    /* compiling/compiling_icode.nit:403 */
      if (!once_value_1) {
        fra.me.REG[0] = BOX_NativeString(" = ");
        REGB0 = TAG_Int(3);
@@ -3200,9 +3312,9 @@ val_t compiling___compiling_icode___ICode___new_result(val_t p0, val_t p1){
      fra.me.REG[0] = fra.me.REG[0];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
    }
-  /* ./compiling//compiling_icode.nit:403 */
+  /* compiling/compiling_icode.nit:405 */
    fra.me.REG[0] = CALL_compiling___compiling_writer___Writer___sub(fra.me.REG[2])(fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:404 */
+  /* compiling/compiling_icode.nit:406 */
    if (!once_value_2) {
      fra.me.REG[1] = BOX_NativeString(";\n");
      REGB0 = TAG_Int(2);
@@ -3212,7 +3324,7 @@ val_t compiling___compiling_icode___ICode___new_result(val_t p0, val_t p1){
    } else fra.me.REG[1] = once_value_2;
    fra.me.REG[1] = fra.me.REG[1];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:405 */
+  /* compiling/compiling_icode.nit:407 */
    goto label3;
    label3: while(0);
    stack_frame_head = fra.me.prev;
@@ -3225,25 +3337,26 @@ void compiling___compiling_icode___ISeq___compile_to_c(val_t p0, val_t p1){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 410;
+  fra.me.line = 412;
    fra.me.meth = LOCATE_compiling___compiling_icode___ISeq___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:412 */
+  /* compiling/compiling_icode.nit:414 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:413 */
+  /* compiling/compiling_icode.nit:415 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___local_labels(fra.me.REG[1])(fra.me.REG[1]);
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:414 */
+  /* compiling/compiling_icode.nit:416 */
    fra.me.REG[2] = CALL_icode___icode_base___ISeq___iescape_mark(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:415 */
+  /* compiling/compiling_icode.nit:417 */
    REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -3261,10 +3374,10 @@ void compiling___compiling_icode___ISeq___compile_to_c(val_t p0, val_t p1){
      fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___marks_to_seq(fra.me.REG[1])(fra.me.REG[1]);
      CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2], fra.me.REG[0]);
    }
-  /* ./compiling//compiling_icode.nit:416 */
+  /* compiling/compiling_icode.nit:418 */
    fra.me.REG[2] = CALL_icode___icode_base___ISeq___icodes(fra.me.REG[0])(fra.me.REG[0]);
    CALL_standard___collection___abstract_collection___Collection___iterate(fra.me.REG[2])(fra.me.REG[2], (&(fra.me)), ((fun_t)OC_compiling___compiling_icode___ISeq___compile_to_c_1));
-  /* ./compiling//compiling_icode.nit:419 */
+  /* compiling/compiling_icode.nit:421 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_label(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
    return;
@@ -3279,12 +3392,13 @@ void compiling___compiling_icode___ISeq___compile_to_c(val_t p0, val_t p1){
      fra.me.meth = LOCATE_compiling___compiling_icode___ISeq___compile_to_c;
      fra.me.has_broke = 0;
      fra.me.REG_size = 1;
+    fra.me.nitni_local_ref_head = NULL;
      fra.me.REG[0] = NIT_NULL;
      fra.me.closure_ctx = closctx_param;
      fra.me.closure_funs = CREG;
      fra.me.REG[0] = p0;
      CREG[0] = clos_fun0;
-    /* ./compiling//compiling_icode.nit:417 */
+    /* compiling/compiling_icode.nit:419 */
      CALL_compiling___compiling_icode___ICode___compile_to_c(fra.me.REG[0])(fra.me.REG[0], closctx->REG[1]);
      stack_frame_head = fra.me.prev;
      return;
@@ -3299,22 +3413,23 @@ void compiling___compiling_icode___IIf___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_4; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 424;
+  fra.me.line = 426;
    fra.me.meth = LOCATE_compiling___compiling_icode___IIf___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:426 */
+  /* compiling/compiling_icode.nit:428 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:427 */
+  /* compiling/compiling_icode.nit:429 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:428 */
+  /* compiling/compiling_icode.nit:430 */
    if (!once_value_1) {
      fra.me.REG[3] = BOX_NativeString("if (UNTAG_Bool(");
      REGB0 = TAG_Int(15);
@@ -3324,11 +3439,11 @@ void compiling___compiling_icode___IIf___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[3] = once_value_1;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:429 */
+  /* compiling/compiling_icode.nit:431 */
    fra.me.REG[3] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:430 */
+  /* compiling/compiling_icode.nit:432 */
    if (!once_value_2) {
      fra.me.REG[3] = BOX_NativeString(")) {\n");
      REGB0 = TAG_Int(5);
@@ -3338,27 +3453,27 @@ void compiling___compiling_icode___IIf___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[3] = once_value_2;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:431 */
+  /* compiling/compiling_icode.nit:433 */
    fra.me.REG[3] = CALL_icode___icode_base___IIf___then_seq(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_icode___icode_base___ISeq___icodes(fra.me.REG[3])(fra.me.REG[3]);
    REGB0 = CALL_standard___collection___abstract_collection___Collection___is_empty(fra.me.REG[3])(fra.me.REG[3]);
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:432 */
+    /* compiling/compiling_icode.nit:434 */
      CALL_compiling___compiling_icode___I2CCompilerVisitor___indent(fra.me.REG[1])(fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:433 */
+    /* compiling/compiling_icode.nit:435 */
      fra.me.REG[3] = CALL_icode___icode_base___IIf___then_seq(fra.me.REG[0])(fra.me.REG[0]);
      CALL_compiling___compiling_icode___ICode___compile_to_c(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:434 */
+    /* compiling/compiling_icode.nit:436 */
      CALL_compiling___compiling_icode___I2CCompilerVisitor___unindent(fra.me.REG[1])(fra.me.REG[1]);
    }
-  /* ./compiling//compiling_icode.nit:436 */
+  /* compiling/compiling_icode.nit:438 */
    fra.me.REG[3] = CALL_icode___icode_base___IIf___else_seq(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_icode___icode_base___ISeq___icodes(fra.me.REG[3])(fra.me.REG[3]);
    REGB0 = CALL_standard___collection___abstract_collection___Collection___is_empty(fra.me.REG[3])(fra.me.REG[3]);
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:437 */
+    /* compiling/compiling_icode.nit:439 */
      if (!once_value_3) {
        fra.me.REG[3] = BOX_NativeString("} else {");
        REGB0 = TAG_Int(8);
@@ -3368,15 +3483,15 @@ void compiling___compiling_icode___IIf___compile_to_c(val_t p0, val_t p1){
      } else fra.me.REG[3] = once_value_3;
      fra.me.REG[3] = fra.me.REG[3];
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:438 */
+    /* compiling/compiling_icode.nit:440 */
      CALL_compiling___compiling_icode___I2CCompilerVisitor___indent(fra.me.REG[1])(fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:439 */
+    /* compiling/compiling_icode.nit:441 */
      fra.me.REG[0] = CALL_icode___icode_base___IIf___else_seq(fra.me.REG[0])(fra.me.REG[0]);
      CALL_compiling___compiling_icode___ICode___compile_to_c(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:440 */
+    /* compiling/compiling_icode.nit:442 */
      CALL_compiling___compiling_icode___I2CCompilerVisitor___unindent(fra.me.REG[1])(fra.me.REG[1]);
    }
-  /* ./compiling//compiling_icode.nit:442 */
+  /* compiling/compiling_icode.nit:444 */
    if (!once_value_4) {
      fra.me.REG[0] = BOX_NativeString("}");
      REGB0 = TAG_Int(1);
@@ -3398,25 +3513,26 @@ void compiling___compiling_icode___ILoop___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 447;
+  fra.me.line = 449;
    fra.me.meth = LOCATE_compiling___compiling_icode___ILoop___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:449 */
+  /* compiling/compiling_icode.nit:451 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:450 */
+  /* compiling/compiling_icode.nit:452 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___local_labels(fra.me.REG[1])(fra.me.REG[1]);
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:451 */
+  /* compiling/compiling_icode.nit:453 */
    fra.me.REG[2] = CALL_icode___icode_base___ISeq___iescape_mark(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:452 */
+  /* compiling/compiling_icode.nit:454 */
    REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -3434,7 +3550,7 @@ void compiling___compiling_icode___ILoop___compile_to_c(val_t p0, val_t p1){
      fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___marks_to_seq(fra.me.REG[1])(fra.me.REG[1]);
      CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2], fra.me.REG[0]);
    }
-  /* ./compiling//compiling_icode.nit:453 */
+  /* compiling/compiling_icode.nit:455 */
    if (!once_value_1) {
      fra.me.REG[2] = BOX_NativeString("while(1) {");
      REGB0 = TAG_Int(10);
@@ -3444,14 +3560,14 @@ void compiling___compiling_icode___ILoop___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[2] = once_value_1;
    fra.me.REG[2] = fra.me.REG[2];
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:454 */
+  /* compiling/compiling_icode.nit:456 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___indent(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:455 */
+  /* compiling/compiling_icode.nit:457 */
    fra.me.REG[2] = CALL_icode___icode_base___ISeq___icodes(fra.me.REG[0])(fra.me.REG[0]);
    CALL_standard___collection___abstract_collection___Collection___iterate(fra.me.REG[2])(fra.me.REG[2], (&(fra.me)), ((fun_t)OC_compiling___compiling_icode___ILoop___compile_to_c_2));
-  /* ./compiling//compiling_icode.nit:458 */
+  /* compiling/compiling_icode.nit:460 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___unindent(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:459 */
+  /* compiling/compiling_icode.nit:461 */
    if (!once_value_3) {
      fra.me.REG[2] = BOX_NativeString("}");
      REGB0 = TAG_Int(1);
@@ -3461,7 +3577,7 @@ void compiling___compiling_icode___ILoop___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[2] = once_value_3;
    fra.me.REG[2] = fra.me.REG[2];
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:460 */
+  /* compiling/compiling_icode.nit:462 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_label(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
    return;
@@ -3476,12 +3592,13 @@ void compiling___compiling_icode___ILoop___compile_to_c(val_t p0, val_t p1){
      fra.me.meth = LOCATE_compiling___compiling_icode___ILoop___compile_to_c;
      fra.me.has_broke = 0;
      fra.me.REG_size = 1;
+    fra.me.nitni_local_ref_head = NULL;
      fra.me.REG[0] = NIT_NULL;
      fra.me.closure_ctx = closctx_param;
      fra.me.closure_funs = CREG;
      fra.me.REG[0] = p0;
      CREG[0] = clos_fun0;
-    /* ./compiling//compiling_icode.nit:456 */
+    /* compiling/compiling_icode.nit:458 */
      CALL_compiling___compiling_icode___ICode___compile_to_c(fra.me.REG[0])(fra.me.REG[0], closctx->REG[1]);
      stack_frame_head = fra.me.prev;
      return;
@@ -3491,19 +3608,20 @@ void compiling___compiling_icode___IEscape___compile_to_c(val_t p0, val_t p1){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 465;
+  fra.me.line = 467;
    fra.me.meth = LOCATE_compiling___compiling_icode___IEscape___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:467 */
+  /* compiling/compiling_icode.nit:469 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:468 */
+  /* compiling/compiling_icode.nit:470 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___marks_to_seq(fra.me.REG[1])(fra.me.REG[1]);
    fra.me.REG[0] = CALL_icode___icode_base___IEscape___iescape_mark(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
@@ -3512,7 +3630,7 @@ void compiling___compiling_icode___IEscape___compile_to_c(val_t p0, val_t p1){
    return;
  }
  void compiling___compiling_icode___IAbsCall___compile_to_c(val_t p0, val_t p1){
-  struct {struct stack_frame_t me; val_t MORE_REG[8];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[9];} fra;
    val_t REGB0;
    val_t REGB1;
    val_t tmp;
@@ -3535,10 +3653,11 @@ void compiling___compiling_icode___IAbsCall___compile_to_c(val_t p0, val_t p1){
        static val_t once_value_20; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 473;
+  fra.me.line = 475;
    fra.me.meth = LOCATE_compiling___compiling_icode___IAbsCall___compile_to_c;
    fra.me.has_broke = 0;
-  fra.me.REG_size = 9;
+  fra.me.REG_size = 10;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -3548,350 +3667,353 @@ void compiling___compiling_icode___IAbsCall___compile_to_c(val_t p0, val_t p1){
    fra.me.REG[6] = NIT_NULL;
    fra.me.REG[7] = NIT_NULL;
    fra.me.REG[8] = NIT_NULL;
+  fra.me.REG[9] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:475 */
-  fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
-  CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:476 */
-  fra.me.REG[2] = CALL_icode___icode_base___ICodeN___exprs(fra.me.REG[0])(fra.me.REG[0]);
-  fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___registers(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:479 */
-  fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:480 */
-  fra.me.REG[4] = CALL_icode___icode_base___ICodeN___closure_defs(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:481 */
-  fra.me.REG[5] = NIT_NULL;
-  /* ./compiling//compiling_icode.nit:482 */
-  REGB0 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
+  /* compiling/compiling_icode.nit:475 */
+  fra.me.REG[2] = fra.me.REG[0];
+  /* compiling/compiling_icode.nit:477 */
+  fra.me.REG[3] = CALL_icode___icode_base___ICode___location(fra.me.REG[2])(fra.me.REG[2]);
+  CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:478 */
+  fra.me.REG[3] = CALL_icode___icode_base___ICodeN___exprs(fra.me.REG[2])(fra.me.REG[2]);
+  fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___registers(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:481 */
+  fra.me.REG[4] = CALL_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels(fra.me.REG[1])(fra.me.REG[1]);
+  /* compiling/compiling_icode.nit:482 */
+  fra.me.REG[5] = CALL_icode___icode_base___ICodeN___closure_defs(fra.me.REG[2])(fra.me.REG[2]);
+  /* compiling/compiling_icode.nit:483 */
+  fra.me.REG[6] = NIT_NULL;
+  /* compiling/compiling_icode.nit:484 */
+  REGB0 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    REGB1 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
+    REGB1 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
        REGB1 = TAG_Bool(false);
        REGB0 = REGB1;
      } else {
-      REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[4])(fra.me.REG[4], NIT_NULL);
+      REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[5])(fra.me.REG[5], NIT_NULL);
        REGB0 = REGB1;
      }
    }
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:484 */
+    /* compiling/compiling_icode.nit:486 */
      REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___closure(fra.me.REG[1])(fra.me.REG[1]);
      if (UNTAG_Bool(REGB0)) {
-      /* ./compiling//compiling_icode.nit:485 */
+      /* compiling/compiling_icode.nit:487 */
        if (!once_value_1) {
-        fra.me.REG[6] = BOX_NativeString("closctx");
+        fra.me.REG[7] = BOX_NativeString("closctx");
          REGB0 = TAG_Int(7);
-        fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB0);
-        once_value_1 = fra.me.REG[6];
+        fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB0);
+        once_value_1 = fra.me.REG[7];
          register_static_object(&once_value_1);
-      } else fra.me.REG[6] = once_value_1;
-      fra.me.REG[6] = fra.me.REG[6];
-      fra.me.REG[5] = fra.me.REG[6];
+      } else fra.me.REG[7] = once_value_1;
+      fra.me.REG[7] = fra.me.REG[7];
+      fra.me.REG[6] = fra.me.REG[7];
      } else {
-      /* ./compiling//compiling_icode.nit:487 */
+      /* compiling/compiling_icode.nit:489 */
        if (!once_value_2) {
-        fra.me.REG[6] = BOX_NativeString("(&(fra.me))");
+        fra.me.REG[7] = BOX_NativeString("(&(fra.me))");
          REGB0 = TAG_Int(11);
-        fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB0);
-        once_value_2 = fra.me.REG[6];
+        fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB0);
+        once_value_2 = fra.me.REG[7];
          register_static_object(&once_value_2);
-      } else fra.me.REG[6] = once_value_2;
-      fra.me.REG[6] = fra.me.REG[6];
-      fra.me.REG[5] = fra.me.REG[6];
+      } else fra.me.REG[7] = once_value_2;
+      fra.me.REG[7] = fra.me.REG[7];
+      fra.me.REG[6] = fra.me.REG[7];
      }
-    /* ./compiling//compiling_icode.nit:491 */
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[5]);
-    /* ./compiling//compiling_icode.nit:494 */
-    fra.me.REG[6] = NEW_HashMap_standard___collection___hash_collection___HashMap___init();
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels__eq(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[6]);
-    /* ./compiling//compiling_icode.nit:497 */
-    REGB0 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
+    /* compiling/compiling_icode.nit:493 */
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[6]);
+    /* compiling/compiling_icode.nit:496 */
+    fra.me.REG[7] = NEW_HashMap_standard___collection___hash_collection___HashMap___init();
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels__eq(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[7]);
+    /* compiling/compiling_icode.nit:499 */
+    REGB0 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 497);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 499);
      }
-    CALL_standard___collection___abstract_collection___Collection___iterate(fra.me.REG[4])(fra.me.REG[4], (&(fra.me)), ((fun_t)OC_compiling___compiling_icode___IAbsCall___compile_to_c_3));
+    CALL_standard___collection___abstract_collection___Collection___iterate(fra.me.REG[5])(fra.me.REG[5], (&(fra.me)), ((fun_t)OC_compiling___compiling_icode___IAbsCall___compile_to_c_3));
    }
-  /* ./compiling//compiling_icode.nit:508 */
-  fra.me.REG[2] = CALL_compiling___compiling_icode___IAbsCall___compile_call_to_c(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:509 */
-  fra.me.REG[4] = fra.me.REG[2];
-  /* ./compiling//compiling_icode.nit:512 */
-  REGB0 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
+  /* compiling/compiling_icode.nit:510 */
+  fra.me.REG[3] = CALL_compiling___compiling_icode___IAbsCall___compile_call_to_c(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1], fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:511 */
+  fra.me.REG[5] = fra.me.REG[3];
+  /* compiling/compiling_icode.nit:514 */
+  REGB0 = TAG_Bool(fra.me.REG[6]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    REGB1 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
+    REGB1 = TAG_Bool(fra.me.REG[6]==NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
        REGB1 = TAG_Bool(false);
        REGB0 = REGB1;
      } else {
-      REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[5])(fra.me.REG[5], NIT_NULL);
+      REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[6])(fra.me.REG[6], NIT_NULL);
        REGB0 = REGB1;
      }
    }
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:513 */
-    fra.me.REG[6] = CALL_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels(fra.me.REG[1])(fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:514 */
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels__eq(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:516 */
-    REGB0 = CALL_standard___collection___abstract_collection___Collection___is_empty(fra.me.REG[6])(fra.me.REG[6]);
+    /* compiling/compiling_icode.nit:515 */
+    fra.me.REG[7] = CALL_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels(fra.me.REG[1])(fra.me.REG[1]);
+    /* compiling/compiling_icode.nit:516 */
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___escaped_labels__eq(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+    /* compiling/compiling_icode.nit:518 */
+    REGB0 = CALL_standard___collection___abstract_collection___MapRead___is_empty(fra.me.REG[7])(fra.me.REG[7]);
      REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
      if (UNTAG_Bool(REGB0)) {
-      /* ./compiling//compiling_icode.nit:518 */
-      fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
-      /* ./compiling//compiling_icode.nit:519 */
-      REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
+      /* compiling/compiling_icode.nit:520 */
+      fra.me.REG[4] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
+      /* compiling/compiling_icode.nit:521 */
+      REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[2])(fra.me.REG[2]);
        if (UNTAG_Bool(REGB0)) {
-        /* ./compiling//compiling_icode.nit:520 */
+        /* compiling/compiling_icode.nit:522 */
          if (!once_value_5) {
-          fra.me.REG[7] = BOX_NativeString("tmp");
+          fra.me.REG[8] = BOX_NativeString("tmp");
            REGB0 = TAG_Int(3);
-          fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB0);
-          once_value_5 = fra.me.REG[7];
+          fra.me.REG[8] = NEW_String_standard___string___String___with_native(fra.me.REG[8], REGB0);
+          once_value_5 = fra.me.REG[8];
            register_static_object(&once_value_5);
-        } else fra.me.REG[7] = once_value_5;
-        fra.me.REG[7] = fra.me.REG[7];
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[7]);
-        /* ./compiling//compiling_icode.nit:521 */
+        } else fra.me.REG[8] = once_value_5;
+        fra.me.REG[8] = fra.me.REG[8];
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[8]);
+        /* compiling/compiling_icode.nit:523 */
          if (!once_value_6) {
-          fra.me.REG[7] = BOX_NativeString(" = ");
+          fra.me.REG[8] = BOX_NativeString(" = ");
            REGB0 = TAG_Int(3);
-          fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB0);
-          once_value_6 = fra.me.REG[7];
+          fra.me.REG[8] = NEW_String_standard___string___String___with_native(fra.me.REG[8], REGB0);
+          once_value_6 = fra.me.REG[8];
            register_static_object(&once_value_6);
-        } else fra.me.REG[7] = once_value_6;
-        fra.me.REG[7] = fra.me.REG[7];
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[7]);
-        /* ./compiling//compiling_icode.nit:522 */
-        CALL_compiling___compiling_writer___Writer___append(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
-        /* ./compiling//compiling_icode.nit:523 */
+        } else fra.me.REG[8] = once_value_6;
+        fra.me.REG[8] = fra.me.REG[8];
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[8]);
+        /* compiling/compiling_icode.nit:524 */
+        CALL_compiling___compiling_writer___Writer___append(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
+        /* compiling/compiling_icode.nit:525 */
          if (!once_value_7) {
-          fra.me.REG[7] = BOX_NativeString(";\n");
+          fra.me.REG[8] = BOX_NativeString(";\n");
            REGB0 = TAG_Int(2);
-          fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB0);
-          once_value_7 = fra.me.REG[7];
+          fra.me.REG[8] = NEW_String_standard___string___String___with_native(fra.me.REG[8], REGB0);
+          once_value_7 = fra.me.REG[8];
            register_static_object(&once_value_7);
-        } else fra.me.REG[7] = once_value_7;
-        fra.me.REG[7] = fra.me.REG[7];
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[7]);
-        /* ./compiling//compiling_icode.nit:524 */
-        fra.me.REG[7] = NEW_Writer_compiling___compiling_writer___Writer___init();
-        fra.me.REG[4] = fra.me.REG[7];
-        /* ./compiling//compiling_icode.nit:525 */
+        } else fra.me.REG[8] = once_value_7;
+        fra.me.REG[8] = fra.me.REG[8];
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[8]);
+        /* compiling/compiling_icode.nit:526 */
+        fra.me.REG[8] = NEW_Writer_compiling___compiling_writer___Writer___init();
+        fra.me.REG[5] = fra.me.REG[8];
+        /* compiling/compiling_icode.nit:527 */
          if (!once_value_8) {
-          fra.me.REG[7] = BOX_NativeString("tmp");
+          fra.me.REG[8] = BOX_NativeString("tmp");
            REGB0 = TAG_Int(3);
-          fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB0);
-          once_value_8 = fra.me.REG[7];
+          fra.me.REG[8] = NEW_String_standard___string___String___with_native(fra.me.REG[8], REGB0);
+          once_value_8 = fra.me.REG[8];
            register_static_object(&once_value_8);
-        } else fra.me.REG[7] = once_value_8;
-        fra.me.REG[7] = fra.me.REG[7];
-        REGB0 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
+        } else fra.me.REG[8] = once_value_8;
+        fra.me.REG[8] = fra.me.REG[8];
+        REGB0 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
          if (UNTAG_Bool(REGB0)) {
-          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 525);
+          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 527);
          }
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[7]);
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[8]);
        } else {
-        /* ./compiling//compiling_icode.nit:527 */
-        fra.me.REG[4] = NIT_NULL;
-        /* ./compiling//compiling_icode.nit:528 */
-        CALL_compiling___compiling_writer___Writer___append(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
-        /* ./compiling//compiling_icode.nit:529 */
+        /* compiling/compiling_icode.nit:529 */
+        fra.me.REG[5] = NIT_NULL;
+        /* compiling/compiling_icode.nit:530 */
+        CALL_compiling___compiling_writer___Writer___append(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
+        /* compiling/compiling_icode.nit:531 */
          if (!once_value_9) {
-          fra.me.REG[2] = BOX_NativeString(";\n");
+          fra.me.REG[3] = BOX_NativeString(";\n");
            REGB0 = TAG_Int(2);
-          fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
-          once_value_9 = fra.me.REG[2];
+          fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+          once_value_9 = fra.me.REG[3];
            register_static_object(&once_value_9);
-        } else fra.me.REG[2] = once_value_9;
-        fra.me.REG[2] = fra.me.REG[2];
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
+        } else fra.me.REG[3] = once_value_9;
+        fra.me.REG[3] = fra.me.REG[3];
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
        }
-      /* ./compiling//compiling_icode.nit:532 */
-      fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
+      /* compiling/compiling_icode.nit:534 */
+      fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
        if (!once_value_10) {
-        fra.me.REG[3] = BOX_NativeString("switch (");
+        fra.me.REG[4] = BOX_NativeString("switch (");
          REGB0 = TAG_Int(8);
-        fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-        once_value_10 = fra.me.REG[3];
+        fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+        once_value_10 = fra.me.REG[4];
          register_static_object(&once_value_10);
-      } else fra.me.REG[3] = once_value_10;
-      fra.me.REG[3] = fra.me.REG[3];
-      fra.me.REG[3] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-      fra.me.REG[3] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[5]);
+      } else fra.me.REG[4] = once_value_10;
+      fra.me.REG[4] = fra.me.REG[4];
+      fra.me.REG[4] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+      fra.me.REG[4] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[6]);
        if (!once_value_11) {
-        fra.me.REG[2] = BOX_NativeString("->has_broke) {\n");
+        fra.me.REG[3] = BOX_NativeString("->has_broke) {\n");
          REGB0 = TAG_Int(15);
-        fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
-        once_value_11 = fra.me.REG[2];
+        fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+        once_value_11 = fra.me.REG[3];
          register_static_object(&once_value_11);
-      } else fra.me.REG[2] = once_value_11;
-      fra.me.REG[2] = fra.me.REG[2];
-      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
-      /* ./compiling//compiling_icode.nit:533 */
+      } else fra.me.REG[3] = once_value_11;
+      fra.me.REG[3] = fra.me.REG[3];
+      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
+      /* compiling/compiling_icode.nit:535 */
        CALL_compiling___compiling_icode___I2CCompilerVisitor___indent(fra.me.REG[1])(fra.me.REG[1]);
-      /* ./compiling//compiling_icode.nit:535 */
+      /* compiling/compiling_icode.nit:537 */
        if (!once_value_12) {
-        fra.me.REG[2] = BOX_NativeString("case 0: break;");
+        fra.me.REG[3] = BOX_NativeString("case 0: break;");
          REGB0 = TAG_Int(14);
-        fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
-        once_value_12 = fra.me.REG[2];
+        fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+        once_value_12 = fra.me.REG[3];
          register_static_object(&once_value_12);
-      } else fra.me.REG[2] = once_value_12;
-      fra.me.REG[2] = fra.me.REG[2];
-      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-      /* ./compiling//compiling_icode.nit:536 */
-      fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___local_labels(fra.me.REG[1])(fra.me.REG[1]);
-      /* ./compiling//compiling_icode.nit:537 */
-      fra.me.REG[6] = CALL_standard___collection___abstract_collection___Collection___iterator(fra.me.REG[6])(fra.me.REG[6]);
-      /* ./compiling//compiling_icode.nit:538 */
+      } else fra.me.REG[3] = once_value_12;
+      fra.me.REG[3] = fra.me.REG[3];
+      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+      /* compiling/compiling_icode.nit:538 */
+      fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___local_labels(fra.me.REG[1])(fra.me.REG[1]);
+      /* compiling/compiling_icode.nit:539 */
+      fra.me.REG[7] = CALL_standard___collection___abstract_collection___MapRead___iterator(fra.me.REG[7])(fra.me.REG[7]);
+      /* compiling/compiling_icode.nit:540 */
        REGB0 = TAG_Bool(false);
-      /* ./compiling//compiling_icode.nit:539 */
+      /* compiling/compiling_icode.nit:541 */
        while(1) {
-        REGB1 = CALL_standard___collection___abstract_collection___Iterator___is_ok(fra.me.REG[6])(fra.me.REG[6]);
+        REGB1 = CALL_standard___collection___abstract_collection___MapIterator___is_ok(fra.me.REG[7])(fra.me.REG[7]);
          if (UNTAG_Bool(REGB1)) {
-          /* ./compiling//compiling_icode.nit:540 */
-          fra.me.REG[3] = CALL_standard___collection___abstract_collection___MapIterator___key(fra.me.REG[6])(fra.me.REG[6]);
-          /* ./compiling//compiling_icode.nit:541 */
-          REGB1 = CALL_standard___collection___abstract_collection___Collection___has(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
+          /* compiling/compiling_icode.nit:542 */
+          fra.me.REG[4] = CALL_standard___collection___abstract_collection___MapIterator___key(fra.me.REG[7])(fra.me.REG[7]);
+          /* compiling/compiling_icode.nit:543 */
+          REGB1 = CALL_standard___collection___abstract_collection___Collection___has(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
            if (UNTAG_Bool(REGB1)) {
-            /* ./compiling//compiling_icode.nit:544 */
-            fra.me.REG[7] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
+            /* compiling/compiling_icode.nit:546 */
+            fra.me.REG[8] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
              if (!once_value_13) {
-              fra.me.REG[8] = BOX_NativeString("case ");
+              fra.me.REG[9] = BOX_NativeString("case ");
                REGB1 = TAG_Int(5);
-              fra.me.REG[8] = NEW_String_standard___string___String___with_native(fra.me.REG[8], REGB1);
-              once_value_13 = fra.me.REG[8];
+              fra.me.REG[9] = NEW_String_standard___string___String___with_native(fra.me.REG[9], REGB1);
+              once_value_13 = fra.me.REG[9];
                register_static_object(&once_value_13);
-            } else fra.me.REG[8] = once_value_13;
-            fra.me.REG[8] = fra.me.REG[8];
-            fra.me.REG[8] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[8]);
-            fra.me.REG[7] = CALL_standard___collection___abstract_collection___Iterator___item(fra.me.REG[6])(fra.me.REG[6]);
-            REGB1 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
+            } else fra.me.REG[9] = once_value_13;
+            fra.me.REG[9] = fra.me.REG[9];
+            fra.me.REG[9] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[9]);
+            fra.me.REG[8] = CALL_standard___collection___abstract_collection___MapIterator___item(fra.me.REG[7])(fra.me.REG[7]);
+            REGB1 = TAG_Bool(fra.me.REG[8]==NIT_NULL);
              if (UNTAG_Bool(REGB1)) {
-              nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 544);
+              nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 546);
              }
-            fra.me.REG[7] = CALL_standard___string___Object___to_s(fra.me.REG[7])(fra.me.REG[7]);
-            fra.me.REG[7] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[7]);
+            fra.me.REG[8] = CALL_standard___string___Object___to_s(fra.me.REG[8])(fra.me.REG[8]);
+            fra.me.REG[8] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[9])(fra.me.REG[9], fra.me.REG[8]);
              if (!once_value_14) {
-              fra.me.REG[8] = BOX_NativeString(": ");
+              fra.me.REG[9] = BOX_NativeString(": ");
                REGB1 = TAG_Int(2);
-              fra.me.REG[8] = NEW_String_standard___string___String___with_native(fra.me.REG[8], REGB1);
-              once_value_14 = fra.me.REG[8];
+              fra.me.REG[9] = NEW_String_standard___string___String___with_native(fra.me.REG[9], REGB1);
+              once_value_14 = fra.me.REG[9];
                register_static_object(&once_value_14);
-            } else fra.me.REG[8] = once_value_14;
-            fra.me.REG[8] = fra.me.REG[8];
-            fra.me.REG[8] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[8]);
-            fra.me.REG[8] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[5]);
+            } else fra.me.REG[9] = once_value_14;
+            fra.me.REG[9] = fra.me.REG[9];
+            fra.me.REG[9] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[9]);
+            fra.me.REG[9] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[9])(fra.me.REG[9], fra.me.REG[6]);
              if (!once_value_15) {
-              fra.me.REG[7] = BOX_NativeString("->has_broke = 0; goto ");
+              fra.me.REG[8] = BOX_NativeString("->has_broke = 0; goto ");
                REGB1 = TAG_Int(22);
-              fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
-              once_value_15 = fra.me.REG[7];
+              fra.me.REG[8] = NEW_String_standard___string___String___with_native(fra.me.REG[8], REGB1);
+              once_value_15 = fra.me.REG[8];
                register_static_object(&once_value_15);
-            } else fra.me.REG[7] = once_value_15;
-            fra.me.REG[7] = fra.me.REG[7];
-            fra.me.REG[7] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[7]);
-            fra.me.REG[8] = CALL_compiling___compiling_icode___I2CCompilerVisitor___lab(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-            fra.me.REG[8] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[8]);
+            } else fra.me.REG[8] = once_value_15;
+            fra.me.REG[8] = fra.me.REG[8];
+            fra.me.REG[8] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[9])(fra.me.REG[9], fra.me.REG[8]);
+            fra.me.REG[9] = CALL_compiling___compiling_icode___I2CCompilerVisitor___lab(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+            fra.me.REG[9] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[9]);
              if (!once_value_16) {
-              fra.me.REG[7] = BOX_NativeString(";\n");
+              fra.me.REG[8] = BOX_NativeString(";\n");
                REGB1 = TAG_Int(2);
-              fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
-              once_value_16 = fra.me.REG[7];
+              fra.me.REG[8] = NEW_String_standard___string___String___with_native(fra.me.REG[8], REGB1);
+              once_value_16 = fra.me.REG[8];
                register_static_object(&once_value_16);
-            } else fra.me.REG[7] = once_value_16;
-            fra.me.REG[7] = fra.me.REG[7];
-            CALL_compiling___compiling_writer___Writer___add(fra.me.REG[8])(fra.me.REG[8], fra.me.REG[7]);
+            } else fra.me.REG[8] = once_value_16;
+            fra.me.REG[8] = fra.me.REG[8];
+            CALL_compiling___compiling_writer___Writer___add(fra.me.REG[9])(fra.me.REG[9], fra.me.REG[8]);
            } else {
-            /* ./compiling//compiling_icode.nit:547 */
+            /* compiling/compiling_icode.nit:549 */
              REGB1 = CALL_compiling___compiling_icode___I2CCompilerVisitor___closure(fra.me.REG[1])(fra.me.REG[1]);
              if (UNTAG_Bool(REGB1)) {
              } else {
-              nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 547);
+              nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 549);
              }
-            /* ./compiling//compiling_icode.nit:548 */
-            CALL_compiling___compiling_icode___I2CCompilerVisitor___register_escape_label(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-            /* ./compiling//compiling_icode.nit:549 */
+            /* compiling/compiling_icode.nit:550 */
+            CALL_compiling___compiling_icode___I2CCompilerVisitor___register_escape_label(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+            /* compiling/compiling_icode.nit:551 */
              REGB1 = TAG_Bool(true);
              REGB0 = REGB1;
            }
-          /* ./compiling//compiling_icode.nit:551 */
-          CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[6])(fra.me.REG[6]);
+          /* compiling/compiling_icode.nit:553 */
+          CALL_standard___collection___abstract_collection___MapIterator___next(fra.me.REG[7])(fra.me.REG[7]);
          } else {
-          /* ./compiling//compiling_icode.nit:539 */
+          /* compiling/compiling_icode.nit:541 */
            goto label17;
          }
        }
        label17: while(0);
-      /* ./compiling//compiling_icode.nit:554 */
+      /* compiling/compiling_icode.nit:556 */
        if (UNTAG_Bool(REGB0)) {
-        /* ./compiling//compiling_icode.nit:557 */
-        fra.me.REG[6] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
+        /* compiling/compiling_icode.nit:559 */
+        fra.me.REG[7] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
          if (!once_value_18) {
-          fra.me.REG[5] = BOX_NativeString("default: goto ");
+          fra.me.REG[6] = BOX_NativeString("default: goto ");
            REGB0 = TAG_Int(14);
-          fra.me.REG[5] = NEW_String_standard___string___String___with_native(fra.me.REG[5], REGB0);
-          once_value_18 = fra.me.REG[5];
+          fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB0);
+          once_value_18 = fra.me.REG[6];
            register_static_object(&once_value_18);
-        } else fra.me.REG[5] = once_value_18;
-        fra.me.REG[5] = fra.me.REG[5];
-        fra.me.REG[5] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[5]);
-        fra.me.REG[6] = CALL_compiling___compiling_icode___I2CCompilerVisitor___return_label(fra.me.REG[1])(fra.me.REG[1]);
-        REGB0 = TAG_Bool(fra.me.REG[6]!=NIT_NULL);
+        } else fra.me.REG[6] = once_value_18;
+        fra.me.REG[6] = fra.me.REG[6];
+        fra.me.REG[6] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[6]);
+        fra.me.REG[7] = CALL_compiling___compiling_icode___I2CCompilerVisitor___return_label(fra.me.REG[1])(fra.me.REG[1]);
+        REGB0 = TAG_Bool(fra.me.REG[7]!=NIT_NULL);
          if (UNTAG_Bool(REGB0)) {
          } else {
-          nit_abort("Cast failed", NULL, LOCATE_compiling___compiling_icode, 557);
+          nit_abort("Cast failed", NULL, LOCATE_compiling___compiling_icode, 559);
          }
-        fra.me.REG[6] = CALL_compiling___compiling_icode___I2CCompilerVisitor___lab(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[6]);
-        fra.me.REG[6] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[6]);
+        fra.me.REG[7] = CALL_compiling___compiling_icode___I2CCompilerVisitor___lab(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[7]);
+        fra.me.REG[7] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
          if (!once_value_19) {
-          fra.me.REG[5] = BOX_NativeString(";\n");
+          fra.me.REG[6] = BOX_NativeString(";\n");
            REGB0 = TAG_Int(2);
-          fra.me.REG[5] = NEW_String_standard___string___String___with_native(fra.me.REG[5], REGB0);
-          once_value_19 = fra.me.REG[5];
+          fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB0);
+          once_value_19 = fra.me.REG[6];
            register_static_object(&once_value_19);
-        } else fra.me.REG[5] = once_value_19;
-        fra.me.REG[5] = fra.me.REG[5];
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[5]);
+        } else fra.me.REG[6] = once_value_19;
+        fra.me.REG[6] = fra.me.REG[6];
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[6]);
        }
-      /* ./compiling//compiling_icode.nit:559 */
+      /* compiling/compiling_icode.nit:561 */
        CALL_compiling___compiling_icode___I2CCompilerVisitor___unindent(fra.me.REG[1])(fra.me.REG[1]);
-      /* ./compiling//compiling_icode.nit:560 */
+      /* compiling/compiling_icode.nit:562 */
        if (!once_value_20) {
-        fra.me.REG[5] = BOX_NativeString("}");
+        fra.me.REG[6] = BOX_NativeString("}");
          REGB0 = TAG_Int(1);
-        fra.me.REG[5] = NEW_String_standard___string___String___with_native(fra.me.REG[5], REGB0);
-        once_value_20 = fra.me.REG[5];
+        fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB0);
+        once_value_20 = fra.me.REG[6];
          register_static_object(&once_value_20);
-      } else fra.me.REG[5] = once_value_20;
-      fra.me.REG[5] = fra.me.REG[5];
-      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
+      } else fra.me.REG[6] = once_value_20;
+      fra.me.REG[6] = fra.me.REG[6];
+      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[6]);
      }
    }
-  /* ./compiling//compiling_icode.nit:564 */
-  REGB0 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
+  /* compiling/compiling_icode.nit:566 */
+  REGB0 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    REGB1 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
+    REGB1 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
        REGB1 = TAG_Bool(false);
        REGB0 = REGB1;
      } else {
-      REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[4])(fra.me.REG[4], NIT_NULL);
+      REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[5])(fra.me.REG[5], NIT_NULL);
        REGB0 = REGB1;
      }
    }
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:565 */
-    fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-    /* ./compiling//compiling_icode.nit:566 */
-    CALL_compiling___compiling_writer___Writer___append(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+    /* compiling/compiling_icode.nit:567 */
+    fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+    /* compiling/compiling_icode.nit:568 */
+    CALL_compiling___compiling_writer___Writer___append(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
    }
    stack_frame_head = fra.me.prev;
    return;
@@ -3909,12 +4031,13 @@ void compiling___compiling_icode___IAbsCall___compile_to_c(val_t p0, val_t p1){
        fra.me.meth = LOCATE_compiling___compiling_icode___IAbsCall___compile_to_c;
        fra.me.has_broke = 0;
        fra.me.REG_size = 1;
+      fra.me.nitni_local_ref_head = NULL;
        fra.me.REG[0] = NIT_NULL;
        fra.me.closure_ctx = closctx_param;
        fra.me.closure_funs = CREG;
        fra.me.REG[0] = p0;
        CREG[0] = clos_fun0;
-      /* ./compiling//compiling_icode.nit:498 */
+      /* compiling/compiling_icode.nit:500 */
        REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
        if (UNTAG_Bool(REGB0)) {
        } else {
@@ -3929,16 +4052,16 @@ void compiling___compiling_icode___IAbsCall___compile_to_c(val_t p0, val_t p1){
        }
        REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
        if (UNTAG_Bool(REGB0)) {
-        /* ./compiling//compiling_icode.nit:499 */
+        /* compiling/compiling_icode.nit:501 */
          REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
          if (UNTAG_Bool(REGB0)) {
-          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 499);
+          nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 501);
          }
          fra.me.REG[0] = CALL_compiling___compiling_icode___IClosureDef___compile_closure(fra.me.REG[0])(fra.me.REG[0], closctx->REG[1]);
-        /* ./compiling//compiling_icode.nit:500 */
-        CALL_standard___collection___abstract_collection___SimpleCollection___add(closctx->REG[2])(closctx->REG[2], fra.me.REG[0]);
+        /* compiling/compiling_icode.nit:502 */
+        CALL_standard___collection___abstract_collection___SimpleCollection___add(closctx->REG[3])(closctx->REG[3], fra.me.REG[0]);
        } else {
-        /* ./compiling//compiling_icode.nit:502 */
+        /* compiling/compiling_icode.nit:504 */
          if (!once_value_4) {
            fra.me.REG[0] = BOX_NativeString("NULL");
            REGB0 = TAG_Int(4);
@@ -3947,7 +4070,7 @@ void compiling___compiling_icode___IAbsCall___compile_to_c(val_t p0, val_t p1){
            register_static_object(&once_value_4);
          } else fra.me.REG[0] = once_value_4;
          fra.me.REG[0] = fra.me.REG[0];
-        CALL_standard___collection___abstract_collection___SimpleCollection___add(closctx->REG[2])(closctx->REG[2], fra.me.REG[0]);
+        CALL_standard___collection___abstract_collection___SimpleCollection___add(closctx->REG[3])(closctx->REG[3], fra.me.REG[0]);
        }
        stack_frame_head = fra.me.prev;
        return;
@@ -3957,289 +4080,317 @@ val_t compiling___compiling_icode___IAbsCall___compile_call_to_c(val_t p0, val_t
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 570;
+  fra.me.line = 572;
    fra.me.meth = LOCATE_compiling___compiling_icode___IAbsCall___compile_call_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 0;
-  /* ./compiling//compiling_icode.nit:570 */
-  nit_abort("Deferred method called", NULL, LOCATE_compiling___compiling_icode, 570);
+  fra.me.nitni_local_ref_head = NULL;
+  /* compiling/compiling_icode.nit:572 */
+  nit_abort("Deferred method called", NULL, LOCATE_compiling___compiling_icode, 572);
    stack_frame_head = fra.me.prev;
    return NIT_NULL;
  }
  val_t compiling___compiling_icode___ICall___compile_call_to_c(val_t p0, val_t p1, val_t p2){
-  struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[4];} fra;
    val_t REGB0;
    val_t tmp;
-    static val_t once_value_1; /* Once value */
-  static val_t once_value_2; /* Once value */
+    static val_t once_value_2; /* Once value */
    static val_t once_value_3; /* Once value */
    static val_t once_value_4; /* Once value */
    static val_t once_value_5; /* Once value */
+  static val_t once_value_6; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 575;
+  fra.me.line = 577;
    fra.me.meth = LOCATE_compiling___compiling_icode___ICall___compile_call_to_c;
    fra.me.has_broke = 0;
-  fra.me.REG_size = 4;
+  fra.me.REG_size = 5;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
+  fra.me.REG[4] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
    fra.me.REG[2] = p2;
-  /* ./compiling//compiling_icode.nit:577 */
+  /* compiling/compiling_icode.nit:579 */
    fra.me.REG[1] = NEW_Writer_compiling___compiling_writer___Writer___init();
-  /* ./compiling//compiling_icode.nit:578 */
+  /* compiling/compiling_icode.nit:583 */
+  REGB0 = CALL_icode___icode_base___IAbsCall___is_explicit_from_extern(fra.me.REG[0])(fra.me.REG[0]);
+  if (UNTAG_Bool(REGB0)) {
+    fra.me.REG[3] = fra.me.REG[1];
+    goto label1;
+  }
+  /* compiling/compiling_icode.nit:585 */
    fra.me.REG[0] = CALL_icode___icode_base___IAbsCall___property(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:579 */
-  fra.me.REG[3] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[0])(fra.me.REG[0]);
-  REGB0 = CALL_metamodel___abstractmetamodel___MMGlobalProperty___is_init(fra.me.REG[3])(fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:586 */
+  fra.me.REG[4] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[0])(fra.me.REG[0]);
+  REGB0 = CALL_metamodel___abstractmetamodel___MMGlobalProperty___is_init(fra.me.REG[4])(fra.me.REG[4]);
    if (UNTAG_Bool(REGB0)) {
-    if (!once_value_1) {
-      fra.me.REG[3] = BOX_NativeString("init_table");
+    if (!once_value_2) {
+      fra.me.REG[4] = BOX_NativeString("init_table");
        REGB0 = TAG_Int(10);
-      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-      once_value_1 = fra.me.REG[3];
-      register_static_object(&once_value_1);
-    } else fra.me.REG[3] = once_value_1;
-    fra.me.REG[3] = fra.me.REG[3];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
+      fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+      once_value_2 = fra.me.REG[4];
+      register_static_object(&once_value_2);
+    } else fra.me.REG[4] = once_value_2;
+    fra.me.REG[4] = fra.me.REG[4];
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
    }
-  /* ./compiling//compiling_icode.nit:580 */
+  /* compiling/compiling_icode.nit:587 */
    fra.me.REG[0] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_base___MMGlobalProperty___meth_call(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:581 */
-  if (!once_value_2) {
+  /* compiling/compiling_icode.nit:588 */
+  if (!once_value_3) {
      fra.me.REG[0] = BOX_NativeString("(");
      REGB0 = TAG_Int(1);
      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
-    once_value_2 = fra.me.REG[0];
-    register_static_object(&once_value_2);
-  } else fra.me.REG[0] = once_value_2;
-  fra.me.REG[0] = fra.me.REG[0];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:582 */
-  fra.me.REG[0] = CALL_standard___collection___abstract_collection___Collection___first(fra.me.REG[2])(fra.me.REG[2]);
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:583 */
-  if (!once_value_3) {
-    fra.me.REG[0] = BOX_NativeString(")(");
-    REGB0 = TAG_Int(2);
-    fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
      once_value_3 = fra.me.REG[0];
      register_static_object(&once_value_3);
    } else fra.me.REG[0] = once_value_3;
    fra.me.REG[0] = fra.me.REG[0];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:584 */
+  /* compiling/compiling_icode.nit:589 */
+  fra.me.REG[0] = CALL_standard___collection___abstract_collection___Collection___first(fra.me.REG[2])(fra.me.REG[2]);
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:590 */
    if (!once_value_4) {
-    fra.me.REG[0] = BOX_NativeString(", ");
+    fra.me.REG[0] = BOX_NativeString(")(");
      REGB0 = TAG_Int(2);
      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
      once_value_4 = fra.me.REG[0];
      register_static_object(&once_value_4);
    } else fra.me.REG[0] = once_value_4;
    fra.me.REG[0] = fra.me.REG[0];
-  CALL_compiling___compiling_writer___Writer___add_all(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:585 */
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:591 */
    if (!once_value_5) {
-    fra.me.REG[0] = BOX_NativeString(")");
-    REGB0 = TAG_Int(1);
+    fra.me.REG[0] = BOX_NativeString(", ");
+    REGB0 = TAG_Int(2);
      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
      once_value_5 = fra.me.REG[0];
      register_static_object(&once_value_5);
    } else fra.me.REG[0] = once_value_5;
    fra.me.REG[0] = fra.me.REG[0];
+  CALL_compiling___compiling_writer___Writer___add_all(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:592 */
+  if (!once_value_6) {
+    fra.me.REG[0] = BOX_NativeString(")");
+    REGB0 = TAG_Int(1);
+    fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
+    once_value_6 = fra.me.REG[0];
+    register_static_object(&once_value_6);
+  } else fra.me.REG[0] = once_value_6;
+  fra.me.REG[0] = fra.me.REG[0];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:586 */
-  goto label6;
-  label6: while(0);
+  /* compiling/compiling_icode.nit:593 */
+  fra.me.REG[3] = fra.me.REG[1];
+  goto label1;
+  label1: while(0);
    stack_frame_head = fra.me.prev;
-  return fra.me.REG[1];
+  return fra.me.REG[3];
  }
  val_t compiling___compiling_icode___ISuper___compile_call_to_c(val_t p0, val_t p1, val_t p2){
-  struct {struct stack_frame_t me; val_t MORE_REG[2];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
    val_t REGB0;
    val_t tmp;
-    static val_t once_value_1; /* Once value */
-  static val_t once_value_2; /* Once value */
+    static val_t once_value_2; /* Once value */
    static val_t once_value_3; /* Once value */
    static val_t once_value_4; /* Once value */
    static val_t once_value_5; /* Once value */
+  static val_t once_value_6; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 591;
+  fra.me.line = 598;
    fra.me.meth = LOCATE_compiling___compiling_icode___ISuper___compile_call_to_c;
    fra.me.has_broke = 0;
-  fra.me.REG_size = 3;
+  fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
+  fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
    fra.me.REG[2] = p2;
-  /* ./compiling//compiling_icode.nit:593 */
+  /* compiling/compiling_icode.nit:602 */
+  REGB0 = CALL_icode___icode_base___IAbsCall___is_explicit_from_extern(fra.me.REG[0])(fra.me.REG[0]);
+  if (UNTAG_Bool(REGB0)) {
+    fra.me.REG[1] = NEW_Writer_compiling___compiling_writer___Writer___init();
+    goto label1;
+  }
+  /* compiling/compiling_icode.nit:604 */
    fra.me.REG[0] = CALL_icode___icode_base___IAbsCall___property(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:594 */
-  fra.me.REG[1] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[0])(fra.me.REG[0]);
-  REGB0 = CALL_metamodel___abstractmetamodel___MMGlobalProperty___is_init(fra.me.REG[1])(fra.me.REG[1]);
+  /* compiling/compiling_icode.nit:605 */
+  fra.me.REG[3] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[0])(fra.me.REG[0]);
+  REGB0 = CALL_metamodel___abstractmetamodel___MMGlobalProperty___is_init(fra.me.REG[3])(fra.me.REG[3]);
    if (UNTAG_Bool(REGB0)) {
-    if (!once_value_1) {
-      fra.me.REG[1] = BOX_NativeString("init_table");
+    if (!once_value_2) {
+      fra.me.REG[3] = BOX_NativeString("init_table");
        REGB0 = TAG_Int(10);
-      fra.me.REG[1] = NEW_String_standard___string___String___with_native(fra.me.REG[1], REGB0);
-      once_value_1 = fra.me.REG[1];
-      register_static_object(&once_value_1);
-    } else fra.me.REG[1] = once_value_1;
-    fra.me.REG[1] = fra.me.REG[1];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+      once_value_2 = fra.me.REG[3];
+      register_static_object(&once_value_2);
+    } else fra.me.REG[3] = once_value_2;
+    fra.me.REG[3] = fra.me.REG[3];
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
    }
-  /* ./compiling//compiling_icode.nit:595 */
-  fra.me.REG[1] = NEW_Writer_compiling___compiling_writer___Writer___init();
-  /* ./compiling//compiling_icode.nit:596 */
+  /* compiling/compiling_icode.nit:606 */
+  fra.me.REG[3] = NEW_Writer_compiling___compiling_writer___Writer___init();
+  /* compiling/compiling_icode.nit:607 */
    fra.me.REG[0] = CALL_compiling___compiling_base___MMLocalProperty___super_meth_call(fra.me.REG[0])(fra.me.REG[0]);
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:597 */
-  if (!once_value_2) {
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:608 */
+  if (!once_value_3) {
      fra.me.REG[0] = BOX_NativeString("(");
      REGB0 = TAG_Int(1);
      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
-    once_value_2 = fra.me.REG[0];
-    register_static_object(&once_value_2);
-  } else fra.me.REG[0] = once_value_2;
-  fra.me.REG[0] = fra.me.REG[0];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:598 */
-  fra.me.REG[0] = CALL_standard___collection___abstract_collection___Collection___first(fra.me.REG[2])(fra.me.REG[2]);
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:599 */
-  if (!once_value_3) {
-    fra.me.REG[0] = BOX_NativeString(")(");
-    REGB0 = TAG_Int(2);
-    fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
      once_value_3 = fra.me.REG[0];
      register_static_object(&once_value_3);
    } else fra.me.REG[0] = once_value_3;
    fra.me.REG[0] = fra.me.REG[0];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:600 */
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:609 */
+  fra.me.REG[0] = CALL_standard___collection___abstract_collection___Collection___first(fra.me.REG[2])(fra.me.REG[2]);
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:610 */
    if (!once_value_4) {
-    fra.me.REG[0] = BOX_NativeString(", ");
+    fra.me.REG[0] = BOX_NativeString(")(");
      REGB0 = TAG_Int(2);
      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
      once_value_4 = fra.me.REG[0];
      register_static_object(&once_value_4);
    } else fra.me.REG[0] = once_value_4;
    fra.me.REG[0] = fra.me.REG[0];
-  CALL_compiling___compiling_writer___Writer___add_all(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:601 */
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:611 */
    if (!once_value_5) {
-    fra.me.REG[0] = BOX_NativeString(")");
-    REGB0 = TAG_Int(1);
+    fra.me.REG[0] = BOX_NativeString(", ");
+    REGB0 = TAG_Int(2);
      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
      once_value_5 = fra.me.REG[0];
      register_static_object(&once_value_5);
    } else fra.me.REG[0] = once_value_5;
    fra.me.REG[0] = fra.me.REG[0];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:602 */
-  goto label6;
-  label6: while(0);
+  CALL_compiling___compiling_writer___Writer___add_all(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:612 */
+  if (!once_value_6) {
+    fra.me.REG[0] = BOX_NativeString(")");
+    REGB0 = TAG_Int(1);
+    fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
+    once_value_6 = fra.me.REG[0];
+    register_static_object(&once_value_6);
+  } else fra.me.REG[0] = once_value_6;
+  fra.me.REG[0] = fra.me.REG[0];
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:613 */
+  fra.me.REG[1] = fra.me.REG[3];
+  goto label1;
+  label1: while(0);
    stack_frame_head = fra.me.prev;
    return fra.me.REG[1];
  }
  val_t compiling___compiling_icode___INew___compile_call_to_c(val_t p0, val_t p1, val_t p2){
-  struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[4];} fra;
    val_t REGB0;
    val_t tmp;
-  static val_t once_value_1; /* Once value */
    static val_t once_value_2; /* Once value */
    static val_t once_value_3; /* Once value */
    static val_t once_value_4; /* Once value */
    static val_t once_value_5; /* Once value */
+  static val_t once_value_6; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 607;
+  fra.me.line = 618;
    fra.me.meth = LOCATE_compiling___compiling_icode___INew___compile_call_to_c;
    fra.me.has_broke = 0;
-  fra.me.REG_size = 4;
+  fra.me.REG_size = 5;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
+  fra.me.REG[4] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
    fra.me.REG[2] = p2;
-  /* ./compiling//compiling_icode.nit:609 */
+  /* compiling/compiling_icode.nit:620 */
    fra.me.REG[1] = NEW_Writer_compiling___compiling_writer___Writer___init();
-  /* ./compiling//compiling_icode.nit:610 */
-  if (!once_value_1) {
-    fra.me.REG[3] = BOX_NativeString("NEW_");
-    REGB0 = TAG_Int(4);
-    fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-    once_value_1 = fra.me.REG[3];
-    register_static_object(&once_value_1);
-  } else fra.me.REG[3] = once_value_1;
-  fra.me.REG[3] = fra.me.REG[3];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:611 */
-  fra.me.REG[3] = CALL_icode___icode_base___INew___stype(fra.me.REG[0])(fra.me.REG[0]);
-  fra.me.REG[3] = CALL_metamodel___static_type___MMType___local_class(fra.me.REG[3])(fra.me.REG[3]);
-  fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:612 */
+  /* compiling/compiling_icode.nit:624 */
+  REGB0 = CALL_icode___icode_base___IAbsCall___is_explicit_from_extern(fra.me.REG[0])(fra.me.REG[0]);
+  if (UNTAG_Bool(REGB0)) {
+    fra.me.REG[3] = fra.me.REG[1];
+    goto label1;
+  }
+  /* compiling/compiling_icode.nit:626 */
    if (!once_value_2) {
-    fra.me.REG[3] = BOX_NativeString("_");
-    REGB0 = TAG_Int(1);
-    fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-    once_value_2 = fra.me.REG[3];
+    fra.me.REG[4] = BOX_NativeString("NEW_");
+    REGB0 = TAG_Int(4);
+    fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+    once_value_2 = fra.me.REG[4];
      register_static_object(&once_value_2);
-  } else fra.me.REG[3] = once_value_2;
-  fra.me.REG[3] = fra.me.REG[3];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:613 */
+  } else fra.me.REG[4] = once_value_2;
+  fra.me.REG[4] = fra.me.REG[4];
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+  /* compiling/compiling_icode.nit:627 */
+  fra.me.REG[4] = CALL_icode___icode_base___INew___stype(fra.me.REG[0])(fra.me.REG[0]);
+  fra.me.REG[4] = CALL_metamodel___static_type___MMType___local_class(fra.me.REG[4])(fra.me.REG[4]);
+  fra.me.REG[4] = CALL_standard___string___Object___to_s(fra.me.REG[4])(fra.me.REG[4]);
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+  /* compiling/compiling_icode.nit:628 */
+  if (!once_value_3) {
+    fra.me.REG[4] = BOX_NativeString("_");
+    REGB0 = TAG_Int(1);
+    fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+    once_value_3 = fra.me.REG[4];
+    register_static_object(&once_value_3);
+  } else fra.me.REG[4] = once_value_3;
+  fra.me.REG[4] = fra.me.REG[4];
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+  /* compiling/compiling_icode.nit:629 */
    fra.me.REG[0] = CALL_icode___icode_base___IAbsCall___property(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_metamodel___abstractmetamodel___MMGlobalProperty___intro(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_base___MMLocalProperty___cname(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:614 */
-  if (!once_value_3) {
+  /* compiling/compiling_icode.nit:630 */
+  if (!once_value_4) {
      fra.me.REG[0] = BOX_NativeString("(");
      REGB0 = TAG_Int(1);
      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
-    once_value_3 = fra.me.REG[0];
-    register_static_object(&once_value_3);
-  } else fra.me.REG[0] = once_value_3;
+    once_value_4 = fra.me.REG[0];
+    register_static_object(&once_value_4);
+  } else fra.me.REG[0] = once_value_4;
    fra.me.REG[0] = fra.me.REG[0];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:615 */
-  if (!once_value_4) {
+  /* compiling/compiling_icode.nit:631 */
+  if (!once_value_5) {
      fra.me.REG[0] = BOX_NativeString(", ");
      REGB0 = TAG_Int(2);
      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
-    once_value_4 = fra.me.REG[0];
-    register_static_object(&once_value_4);
-  } else fra.me.REG[0] = once_value_4;
+    once_value_5 = fra.me.REG[0];
+    register_static_object(&once_value_5);
+  } else fra.me.REG[0] = once_value_5;
    fra.me.REG[0] = fra.me.REG[0];
    CALL_compiling___compiling_writer___Writer___add_all(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:616 */
-  if (!once_value_5) {
+  /* compiling/compiling_icode.nit:632 */
+  if (!once_value_6) {
      fra.me.REG[0] = BOX_NativeString(")");
      REGB0 = TAG_Int(1);
      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
-    once_value_5 = fra.me.REG[0];
-    register_static_object(&once_value_5);
-  } else fra.me.REG[0] = once_value_5;
+    once_value_6 = fra.me.REG[0];
+    register_static_object(&once_value_6);
+  } else fra.me.REG[0] = once_value_6;
    fra.me.REG[0] = fra.me.REG[0];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:617 */
-  goto label6;
-  label6: while(0);
+  /* compiling/compiling_icode.nit:633 */
+  fra.me.REG[3] = fra.me.REG[1];
+  goto label1;
+  label1: while(0);
    stack_frame_head = fra.me.prev;
-  return fra.me.REG[1];
+  return fra.me.REG[3];
  }
  void compiling___compiling_icode___IAllocateInstance___compile_to_c(val_t p0, val_t p1){
    struct {struct stack_frame_t me; val_t MORE_REG[2];} fra;
@@ -4249,21 +4400,22 @@ void compiling___compiling_icode___IAllocateInstance___compile_to_c(val_t p0, va
    static val_t once_value_2; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 622;
+  fra.me.line = 638;
    fra.me.meth = LOCATE_compiling___compiling_icode___IAllocateInstance___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:624 */
+  /* compiling/compiling_icode.nit:640 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:625 */
+  /* compiling/compiling_icode.nit:641 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:626 */
+  /* compiling/compiling_icode.nit:642 */
    if (!once_value_1) {
      fra.me.REG[2] = BOX_NativeString("NEW_");
      REGB0 = TAG_Int(4);
@@ -4273,12 +4425,12 @@ void compiling___compiling_icode___IAllocateInstance___compile_to_c(val_t p0, va
    } else fra.me.REG[2] = once_value_1;
    fra.me.REG[2] = fra.me.REG[2];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:627 */
+  /* compiling/compiling_icode.nit:643 */
    fra.me.REG[0] = CALL_icode___icode_base___IAllocateInstance___stype(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_metamodel___static_type___MMType___local_class(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_base___MMLocalClass___cname(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:628 */
+  /* compiling/compiling_icode.nit:644 */
    if (!once_value_2) {
      fra.me.REG[0] = BOX_NativeString("()");
      REGB0 = TAG_Int(2);
@@ -4300,22 +4452,23 @@ void compiling___compiling_icode___ICheckInstance___compile_to_c(val_t p0, val_t
    static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 633;
+  fra.me.line = 649;
    fra.me.meth = LOCATE_compiling___compiling_icode___ICheckInstance___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:635 */
+  /* compiling/compiling_icode.nit:651 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:636 */
+  /* compiling/compiling_icode.nit:652 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:637 */
+  /* compiling/compiling_icode.nit:653 */
    if (!once_value_1) {
      fra.me.REG[3] = BOX_NativeString("CHECKNEW_");
      REGB0 = TAG_Int(9);
@@ -4325,12 +4478,12 @@ void compiling___compiling_icode___ICheckInstance___compile_to_c(val_t p0, val_t
    } else fra.me.REG[3] = once_value_1;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:638 */
+  /* compiling/compiling_icode.nit:654 */
    fra.me.REG[3] = CALL_icode___icode_base___ICheckInstance___stype(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_metamodel___static_type___MMType___local_class(fra.me.REG[3])(fra.me.REG[3]);
    fra.me.REG[3] = CALL_compiling___compiling_base___MMLocalClass___cname(fra.me.REG[3])(fra.me.REG[3]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:639 */
+  /* compiling/compiling_icode.nit:655 */
    if (!once_value_2) {
      fra.me.REG[3] = BOX_NativeString("(");
      REGB0 = TAG_Int(1);
@@ -4340,11 +4493,11 @@ void compiling___compiling_icode___ICheckInstance___compile_to_c(val_t p0, val_t
    } else fra.me.REG[3] = once_value_2;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:640 */
+  /* compiling/compiling_icode.nit:656 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:641 */
+  /* compiling/compiling_icode.nit:657 */
    if (!once_value_3) {
      fra.me.REG[0] = BOX_NativeString(")");
      REGB0 = TAG_Int(1);
@@ -4366,22 +4519,23 @@ void compiling___compiling_icode___IInitAttributes___compile_to_c(val_t p0, val_
    static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 646;
+  fra.me.line = 662;
    fra.me.meth = LOCATE_compiling___compiling_icode___IInitAttributes___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:648 */
+  /* compiling/compiling_icode.nit:664 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:649 */
+  /* compiling/compiling_icode.nit:665 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:650 */
+  /* compiling/compiling_icode.nit:666 */
    if (!once_value_1) {
      fra.me.REG[3] = BOX_NativeString("INIT_ATTRIBUTES__");
      REGB0 = TAG_Int(17);
@@ -4391,12 +4545,12 @@ void compiling___compiling_icode___IInitAttributes___compile_to_c(val_t p0, val_
    } else fra.me.REG[3] = once_value_1;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:651 */
+  /* compiling/compiling_icode.nit:667 */
    fra.me.REG[3] = CALL_icode___icode_base___IInitAttributes___stype(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_metamodel___static_type___MMType___local_class(fra.me.REG[3])(fra.me.REG[3]);
    fra.me.REG[3] = CALL_compiling___compiling_base___MMLocalClass___cname(fra.me.REG[3])(fra.me.REG[3]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:652 */
+  /* compiling/compiling_icode.nit:668 */
    if (!once_value_2) {
      fra.me.REG[3] = BOX_NativeString("(");
      REGB0 = TAG_Int(1);
@@ -4406,11 +4560,11 @@ void compiling___compiling_icode___IInitAttributes___compile_to_c(val_t p0, val_
    } else fra.me.REG[3] = once_value_2;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:653 */
+  /* compiling/compiling_icode.nit:669 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:654 */
+  /* compiling/compiling_icode.nit:670 */
    if (!once_value_3) {
      fra.me.REG[0] = BOX_NativeString(");\n");
      REGB0 = TAG_Int(3);
@@ -4433,19 +4587,20 @@ val_t compiling___compiling_icode___IStaticCall___compile_call_to_c(val_t p0, va
    static val_t once_value_4; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 659;
+  fra.me.line = 675;
    fra.me.meth = LOCATE_compiling___compiling_icode___IStaticCall___compile_call_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
    fra.me.REG[2] = p2;
-  /* ./compiling//compiling_icode.nit:661 */
+  /* compiling/compiling_icode.nit:677 */
    fra.me.REG[1] = CALL_icode___icode_base___IAbsCall___property(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:662 */
+  /* compiling/compiling_icode.nit:678 */
    fra.me.REG[1] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[1])(fra.me.REG[1]);
    REGB0 = CALL_metamodel___abstractmetamodel___MMGlobalProperty___is_init(fra.me.REG[1])(fra.me.REG[1]);
    if (UNTAG_Bool(REGB0)) {
@@ -4459,13 +4614,13 @@ val_t compiling___compiling_icode___IStaticCall___compile_call_to_c(val_t p0, va
      fra.me.REG[1] = fra.me.REG[1];
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
    }
-  /* ./compiling//compiling_icode.nit:663 */
+  /* compiling/compiling_icode.nit:679 */
    fra.me.REG[1] = NEW_Writer_compiling___compiling_writer___Writer___init();
-  /* ./compiling//compiling_icode.nit:664 */
+  /* compiling/compiling_icode.nit:680 */
    fra.me.REG[0] = CALL_icode___icode_base___IAbsCall___property(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_base___MMLocalProperty___cname(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:665 */
+  /* compiling/compiling_icode.nit:681 */
    if (!once_value_2) {
      fra.me.REG[0] = BOX_NativeString("(");
      REGB0 = TAG_Int(1);
@@ -4475,7 +4630,7 @@ val_t compiling___compiling_icode___IStaticCall___compile_call_to_c(val_t p0, va
    } else fra.me.REG[0] = once_value_2;
    fra.me.REG[0] = fra.me.REG[0];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:666 */
+  /* compiling/compiling_icode.nit:682 */
    if (!once_value_3) {
      fra.me.REG[0] = BOX_NativeString(", ");
      REGB0 = TAG_Int(2);
@@ -4485,7 +4640,7 @@ val_t compiling___compiling_icode___IStaticCall___compile_call_to_c(val_t p0, va
    } else fra.me.REG[0] = once_value_3;
    fra.me.REG[0] = fra.me.REG[0];
    CALL_compiling___compiling_writer___Writer___add_all(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:667 */
+  /* compiling/compiling_icode.nit:683 */
    if (!once_value_4) {
      fra.me.REG[0] = BOX_NativeString(")");
      REGB0 = TAG_Int(1);
@@ -4495,7 +4650,7 @@ val_t compiling___compiling_icode___IStaticCall___compile_call_to_c(val_t p0, va
    } else fra.me.REG[0] = once_value_4;
    fra.me.REG[0] = fra.me.REG[0];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:668 */
+  /* compiling/compiling_icode.nit:684 */
    goto label5;
    label5: while(0);
    stack_frame_head = fra.me.prev;
@@ -4507,31 +4662,33 @@ void compiling___compiling_icode___INative___compile_to_c(val_t p0, val_t p1){
    val_t tmp;
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 673;
+  fra.me.line = 689;
    fra.me.meth = LOCATE_compiling___compiling_icode___INative___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:675 */
+  /* compiling/compiling_icode.nit:691 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:676 */
+  /* compiling/compiling_icode.nit:692 */
    fra.me.REG[2] = CALL_icode___icode_base___INative___method(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = CALL_metamodel___abstractmetamodel___MMMethod___is_intern(fra.me.REG[2])(fra.me.REG[2]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:677 */
+    /* compiling/compiling_icode.nit:693 */
      CALL_compiling___compiling_icode___INative___compile_intern_method_to_c(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
    } else {
-    /* ./compiling//compiling_icode.nit:678 */
+    /* compiling/compiling_icode.nit:694 */
      fra.me.REG[2] = CALL_icode___icode_base___INative___method(fra.me.REG[0])(fra.me.REG[0]);
-    REGB0 = CALL_syntax___syntax_base___MMLocalProperty___is_init(fra.me.REG[2])(fra.me.REG[2]);
+    fra.me.REG[2] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[2])(fra.me.REG[2]);
+    REGB0 = CALL_metamodel___abstractmetamodel___MMGlobalProperty___is_init(fra.me.REG[2])(fra.me.REG[2]);
      REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
      if (UNTAG_Bool(REGB0)) {
-      /* ./compiling//compiling_icode.nit:679 */
+      /* compiling/compiling_icode.nit:695 */
        CALL_compiling___compiling_icode___INative___compile_extern_method_to_c(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
      }
    }
@@ -4554,10 +4711,11 @@ void compiling___compiling_icode___INative___compile_extern_method_to_c(val_t p0
    static val_t once_value_9; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 683;
+  fra.me.line = 699;
    fra.me.meth = LOCATE_compiling___compiling_icode___INative___compile_extern_method_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 7;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -4567,7 +4725,7 @@ void compiling___compiling_icode___INative___compile_extern_method_to_c(val_t p0
    fra.me.REG[6] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:685 */
+  /* compiling/compiling_icode.nit:701 */
    REGB0 = TAG_Int(3);
    fra.me.REG[2] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    if (!once_value_1) {
@@ -4582,7 +4740,7 @@ void compiling___compiling_icode___INative___compile_extern_method_to_c(val_t p0
    fra.me.REG[3] = CALL_icode___icode_base___INative___method(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[4] = CALL_icode___icode_base___INative___method(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[4] = CALL_metamodel___abstractmetamodel___MMLocalProperty___local_class(fra.me.REG[4])(fra.me.REG[4]);
-  fra.me.REG[4] = CALL_syntax___mmbuilder___MMMethod___friendly_extern_name(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+  fra.me.REG[4] = CALL_primitive_info___MMMethod___friendly_extern_name(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
    if (!once_value_2) {
      fra.me.REG[4] = BOX_NativeString("___out");
@@ -4594,148 +4752,173 @@ void compiling___compiling_icode___INative___compile_extern_method_to_c(val_t p0
    fra.me.REG[4] = fra.me.REG[4];
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
    fra.me.REG[2] = CALL_standard___string___Object___to_s(fra.me.REG[2])(fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:687 */
+  /* compiling/compiling_icode.nit:703 */
    fra.me.REG[4] = CALL_icode___icode_base___INative___method(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[4] = CALL_metamodel___static_type___MMLocalProperty___signature(fra.me.REG[4])(fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:688 */
+  /* compiling/compiling_icode.nit:704 */
    fra.me.REG[3] = CALL_icode___icode_base___ICodeN___exprs(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = CALL_standard___collection___abstract_collection___Collection___length(fra.me.REG[3])(fra.me.REG[3]);
    REGB1 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
    if (UNTAG_Bool(REGB1)) {
-    nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 688);
+    nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 704);
    }
    REGB1 = CALL_metamodel___static_type___MMSignature___arity(fra.me.REG[4])(fra.me.REG[4]);
    REGB2 = TAG_Int(1);
-  /* ./../lib/standard//kernel.nit:218 */
+  /* ../lib/standard/kernel.nit:235 */
    REGB2 = TAG_Int(UNTAG_Int(REGB1)+UNTAG_Int(REGB2));
-  /* ./compiling//compiling_icode.nit:688 */
+  /* compiling/compiling_icode.nit:704 */
    REGB1 = TAG_Bool(IS_EQUAL_OO(REGB0,REGB2));
    if (UNTAG_Bool(REGB1)) {
    } else {
-    /* ./../lib/standard//kernel.nit:210 */
+    /* ../lib/standard/kernel.nit:227 */
      REGB2 = TAG_Bool((REGB0)==(REGB2));
-    /* ./compiling//compiling_icode.nit:688 */
+    /* compiling/compiling_icode.nit:704 */
      REGB1 = REGB2;
    }
    if (UNTAG_Bool(REGB1)) {
    } else {
-    nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 688);
+    nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 704);
    }
-  /* ./compiling//compiling_icode.nit:690 */
+  /* compiling/compiling_icode.nit:706 */
    fra.me.REG[3] = CALL_icode___icode_base___ICodeN___exprs(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___registers(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:692 */
+  /* compiling/compiling_icode.nit:708 */
    fra.me.REG[5] = NEW_Array_standard___collection___array___Array___init();
-  /* ./compiling//compiling_icode.nit:693 */
+  /* compiling/compiling_icode.nit:709 */
    REGB1 = TAG_Int(0);
-  /* ./../lib/standard//collection//array.nit:243 */
+  /* ../lib/standard/collection/array.nit:278 */
    fra.me.REG[6] = fra.me.REG[3];
-  /* ./../lib/standard//collection//array.nit:245 */
+  /* ../lib/standard/collection/array.nit:280 */
    REGB2 = TAG_Int(0);
-  /* ./../lib/standard//kernel.nit:216 */
+  REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+  if (UNTAG_Bool(REGB0)) {
+  } else {
+    nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+  }
+  /* ../lib/standard/kernel.nit:233 */
    REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-  /* ./../lib/standard//collection//array.nit:245 */
+  /* ../lib/standard/collection/array.nit:280 */
    if (UNTAG_Bool(REGB2)) {
      REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[6])!=NIT_NULL);
      if (UNTAG_Bool(REGB2)) {
      } else {
-      nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+      nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
      }
      REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[6]);
-    /* ./../lib/standard//kernel.nit:215 */
+    REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+    if (UNTAG_Bool(REGB0)) {
+    } else {
+      nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+    }
+    /* ../lib/standard/kernel.nit:232 */
      REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
    } else {
-    /* ./../lib/standard//collection//array.nit:245 */
+    /* ../lib/standard/collection/array.nit:280 */
      REGB0 = TAG_Bool(false);
      REGB2 = REGB0;
    }
    if (UNTAG_Bool(REGB2)) {
    } else {
-    nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+    nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
    }
-  /* ./../lib/standard//collection//array.nit:246 */
+  /* ../lib/standard/collection/array.nit:281 */
    fra.me.REG[6] = ATTR_standard___collection___array___Array____items(fra.me.REG[6]);
    REGB2 = TAG_Bool(fra.me.REG[6]==NIT_NULL);
    if (UNTAG_Bool(REGB2)) {
-    nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+    nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
    }
-  /* ./../lib/standard//collection//array.nit:654 */
+  /* ../lib/standard/collection/array.nit:718 */
    fra.me.REG[6] = ((Nit_NativeArray)fra.me.REG[6])->val[UNTAG_Int(REGB1)];
-  /* ./../lib/standard//collection//array.nit:246 */
+  /* ../lib/standard/collection/array.nit:281 */
    goto label3;
    label3: while(0);
-  /* ./compiling//compiling_icode.nit:693 */
+  /* compiling/compiling_icode.nit:709 */
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[6]);
-  /* ./compiling//compiling_icode.nit:694 */
+  /* compiling/compiling_icode.nit:710 */
    REGB1 = TAG_Int(0);
    REGB2 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
    if (UNTAG_Bool(REGB2)) {
-    nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 694);
+    nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 710);
    }
    REGB2 = CALL_metamodel___static_type___MMSignature___arity(fra.me.REG[4])(fra.me.REG[4]);
-  /* ./../lib/standard//kernel.nit:335 */
+  /* ../lib/standard/kernel.nit:352 */
    while(1) {
-    /* ./../lib/standard//kernel.nit:215 */
+    REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+    if (UNTAG_Bool(REGB0)) {
+    } else {
+      nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+    }
+    /* ../lib/standard/kernel.nit:232 */
      REGB0 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
-    /* ./../lib/standard//kernel.nit:335 */
+    /* ../lib/standard/kernel.nit:352 */
      if (UNTAG_Bool(REGB0)) {
-      /* ./compiling//compiling_icode.nit:694 */
+      /* compiling/compiling_icode.nit:710 */
        REGB0 = REGB1;
-      /* ./compiling//compiling_icode.nit:695 */
+      /* compiling/compiling_icode.nit:711 */
        REGB3 = TAG_Int(1);
-      /* ./../lib/standard//kernel.nit:218 */
+      /* ../lib/standard/kernel.nit:235 */
        REGB3 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB3));
-      /* ./../lib/standard//collection//array.nit:243 */
+      /* ../lib/standard/collection/array.nit:278 */
        fra.me.REG[4] = fra.me.REG[3];
-      /* ./../lib/standard//collection//array.nit:245 */
+      /* ../lib/standard/collection/array.nit:280 */
        REGB0 = TAG_Int(0);
-      /* ./../lib/standard//kernel.nit:216 */
+      REGB4 = TAG_Bool(VAL_ISA(REGB0, VTCOLOR_standard___kernel___Comparable___OTHER(REGB3), VTID_standard___kernel___Comparable___OTHER(REGB3))) /*cast OTHER*/;
+      if (UNTAG_Bool(REGB4)) {
+      } else {
+        nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+      }
+      /* ../lib/standard/kernel.nit:233 */
        REGB0 = TAG_Bool(UNTAG_Int(REGB3)>=UNTAG_Int(REGB0));
-      /* ./../lib/standard//collection//array.nit:245 */
+      /* ../lib/standard/collection/array.nit:280 */
        if (UNTAG_Bool(REGB0)) {
          REGB0 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[4])!=NIT_NULL);
          if (UNTAG_Bool(REGB0)) {
          } else {
-          nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+          nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
          }
          REGB0 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[4]);
-        /* ./../lib/standard//kernel.nit:215 */
+        REGB4 = TAG_Bool(VAL_ISA(REGB0, VTCOLOR_standard___kernel___Comparable___OTHER(REGB3), VTID_standard___kernel___Comparable___OTHER(REGB3))) /*cast OTHER*/;
+        if (UNTAG_Bool(REGB4)) {
+        } else {
+          nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+        }
+        /* ../lib/standard/kernel.nit:232 */
          REGB0 = TAG_Bool(UNTAG_Int(REGB3)<UNTAG_Int(REGB0));
        } else {
-        /* ./../lib/standard//collection//array.nit:245 */
+        /* ../lib/standard/collection/array.nit:280 */
          REGB4 = TAG_Bool(false);
          REGB0 = REGB4;
        }
        if (UNTAG_Bool(REGB0)) {
        } else {
-        nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+        nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
        }
-      /* ./../lib/standard//collection//array.nit:246 */
+      /* ../lib/standard/collection/array.nit:281 */
        fra.me.REG[4] = ATTR_standard___collection___array___Array____items(fra.me.REG[4]);
        REGB0 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
        if (UNTAG_Bool(REGB0)) {
-        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
        }
-      /* ./../lib/standard//collection//array.nit:654 */
+      /* ../lib/standard/collection/array.nit:718 */
        fra.me.REG[4] = ((Nit_NativeArray)fra.me.REG[4])->val[UNTAG_Int(REGB3)];
-      /* ./../lib/standard//collection//array.nit:246 */
+      /* ../lib/standard/collection/array.nit:281 */
        goto label4;
        label4: while(0);
-      /* ./compiling//compiling_icode.nit:695 */
+      /* compiling/compiling_icode.nit:711 */
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[4]);
-      /* ./../lib/standard//kernel.nit:337 */
+      /* ../lib/standard/kernel.nit:354 */
        REGB3 = TAG_Int(1);
-      /* ./../lib/standard//kernel.nit:218 */
+      /* ../lib/standard/kernel.nit:235 */
        REGB3 = TAG_Int(UNTAG_Int(REGB1)+UNTAG_Int(REGB3));
-      /* ./../lib/standard//kernel.nit:337 */
+      /* ../lib/standard/kernel.nit:354 */
        REGB1 = REGB3;
      } else {
-      /* ./../lib/standard//kernel.nit:335 */
+      /* ../lib/standard/kernel.nit:352 */
        goto label5;
      }
    }
    label5: while(0);
-  /* ./compiling//compiling_icode.nit:697 */
+  /* compiling/compiling_icode.nit:713 */
    REGB1 = TAG_Int(5);
    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
    if (!once_value_6) {
@@ -4777,13 +4960,13 @@ void compiling___compiling_icode___INative___compile_extern_method_to_c(val_t p0
    fra.me.REG[2] = fra.me.REG[2];
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:699 */
+  /* compiling/compiling_icode.nit:715 */
    REGB1 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
    if (UNTAG_Bool(REGB1)) {
    }
-  /* ./compiling//compiling_icode.nit:700 */
+  /* compiling/compiling_icode.nit:716 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:701 */
+  /* compiling/compiling_icode.nit:717 */
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
    stack_frame_head = fra.me.prev;
    return;
@@ -5117,17 +5300,18 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                static val_t once_value_433; /* Once value */
                 static val_t once_value_434; /* Once value */
                 static val_t once_value_435; /* Once value */
+               static val_t once_value_436; /* Once value */
                 static val_t once_value_437; /* Once value */
                 static val_t once_value_438; /* Once value */
                 static val_t once_value_439; /* Once value */
                 static val_t once_value_440; /* Once value */
-               static val_t once_value_441; /* Once value */
                 static val_t once_value_442; /* Once value */
                 static val_t once_value_443; /* Once value */
+               static val_t once_value_444; /* Once value */
                 static val_t once_value_445; /* Once value */
+               static val_t once_value_446; /* Once value */
                 static val_t once_value_447; /* Once value */
                 static val_t once_value_448; /* Once value */
-               static val_t once_value_449; /* Once value */
                 static val_t once_value_450; /* Once value */
                 static val_t once_value_452; /* Once value */
                 static val_t once_value_453; /* Once value */
@@ -5146,19 +5330,24 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 static val_t once_value_469; /* Once value */
                 static val_t once_value_470; /* Once value */
                 static val_t once_value_472; /* Once value */
-      static val_t once_value_473; /* Once value */
-      static val_t once_value_474; /* Once value */
-    static val_t once_value_475; /* Once value */
-    static val_t once_value_476; /* Once value */
-    static val_t once_value_477; /* Once value */
-    static val_t once_value_478; /* Once value */
-    static val_t once_value_479; /* Once value */
+               static val_t once_value_473; /* Once value */
+               static val_t once_value_474; /* Once value */
+               static val_t once_value_475; /* Once value */
+               static val_t once_value_477; /* Once value */
+      static val_t once_value_478; /* Once value */
+      static val_t once_value_479; /* Once value */
+    static val_t once_value_480; /* Once value */
+    static val_t once_value_481; /* Once value */
+    static val_t once_value_482; /* Once value */
+    static val_t once_value_483; /* Once value */
+    static val_t once_value_484; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 704;
+  fra.me.line = 720;
    fra.me.meth = LOCATE_compiling___compiling_icode___INative___compile_intern_method_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 8;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -5169,46 +5358,46 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
    fra.me.REG[7] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:706 */
+  /* compiling/compiling_icode.nit:722 */
    fra.me.REG[2] = CALL_icode___icode_base___INative___method(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[2] = CALL_metamodel___static_type___MMLocalProperty___signature(fra.me.REG[2])(fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:707 */
+  /* compiling/compiling_icode.nit:723 */
    fra.me.REG[3] = CALL_icode___icode_base___ICodeN___exprs(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = CALL_standard___collection___abstract_collection___Collection___length(fra.me.REG[3])(fra.me.REG[3]);
    REGB1 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
    if (UNTAG_Bool(REGB1)) {
-    nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 707);
+    nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 723);
    }
    REGB1 = CALL_metamodel___static_type___MMSignature___arity(fra.me.REG[2])(fra.me.REG[2]);
    REGB2 = TAG_Int(1);
-  /* ./../lib/standard//kernel.nit:218 */
+  /* ../lib/standard/kernel.nit:235 */
    REGB2 = TAG_Int(UNTAG_Int(REGB1)+UNTAG_Int(REGB2));
-  /* ./compiling//compiling_icode.nit:707 */
+  /* compiling/compiling_icode.nit:723 */
    REGB1 = TAG_Bool(IS_EQUAL_OO(REGB0,REGB2));
    if (UNTAG_Bool(REGB1)) {
    } else {
-    /* ./../lib/standard//kernel.nit:210 */
+    /* ../lib/standard/kernel.nit:227 */
      REGB2 = TAG_Bool((REGB0)==(REGB2));
-    /* ./compiling//compiling_icode.nit:707 */
+    /* compiling/compiling_icode.nit:723 */
      REGB1 = REGB2;
    }
    if (UNTAG_Bool(REGB1)) {
    } else {
-    nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 707);
+    nit_abort("Assert failed", NULL, LOCATE_compiling___compiling_icode, 723);
    }
-  /* ./compiling//compiling_icode.nit:708 */
+  /* compiling/compiling_icode.nit:724 */
    fra.me.REG[2] = CALL_icode___icode_base___INative___method(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[2] = CALL_metamodel___abstractmetamodel___MMLocalProperty___local_class(fra.me.REG[2])(fra.me.REG[2]);
    fra.me.REG[2] = CALL_metamodel___abstractmetamodel___MMLocalClass___name(fra.me.REG[2])(fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:709 */
+  /* compiling/compiling_icode.nit:725 */
    fra.me.REG[3] = CALL_icode___icode_base___INative___method(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_metamodel___abstractmetamodel___MMLocalProperty___name(fra.me.REG[3])(fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:710 */
+  /* compiling/compiling_icode.nit:726 */
    fra.me.REG[4] = CALL_icode___icode_base___ICodeN___exprs(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[4] = CALL_compiling___compiling_icode___I2CCompilerVisitor___registers(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:711 */
+  /* compiling/compiling_icode.nit:727 */
    fra.me.REG[5] = NIT_NULL;
-  /* ./compiling//compiling_icode.nit:712 */
+  /* compiling/compiling_icode.nit:728 */
    if (!once_value_1) {
      if (!once_value_2) {
        fra.me.REG[6] = BOX_NativeString("Int");
@@ -5230,7 +5419,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
      REGB1 = REGB2;
    }
    if (UNTAG_Bool(REGB1)) {
-    /* ./compiling//compiling_icode.nit:713 */
+    /* compiling/compiling_icode.nit:729 */
      if (!once_value_3) {
        if (!once_value_4) {
          fra.me.REG[6] = BOX_NativeString("object_id");
@@ -5252,48 +5441,58 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
        REGB1 = REGB2;
      }
      if (UNTAG_Bool(REGB1)) {
-      /* ./compiling//compiling_icode.nit:714 */
+      /* compiling/compiling_icode.nit:730 */
        REGB1 = TAG_Int(0);
-      /* ./../lib/standard//collection//array.nit:243 */
+      /* ../lib/standard/collection/array.nit:278 */
        fra.me.REG[6] = fra.me.REG[4];
-      /* ./../lib/standard//collection//array.nit:245 */
+      /* ../lib/standard/collection/array.nit:280 */
        REGB2 = TAG_Int(0);
-      /* ./../lib/standard//kernel.nit:216 */
+      REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+      if (UNTAG_Bool(REGB0)) {
+      } else {
+        nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+      }
+      /* ../lib/standard/kernel.nit:233 */
        REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-      /* ./../lib/standard//collection//array.nit:245 */
+      /* ../lib/standard/collection/array.nit:280 */
        if (UNTAG_Bool(REGB2)) {
          REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[6])!=NIT_NULL);
          if (UNTAG_Bool(REGB2)) {
          } else {
-          nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+          nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
          }
          REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[6]);
-        /* ./../lib/standard//kernel.nit:215 */
+        REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+        if (UNTAG_Bool(REGB0)) {
+        } else {
+          nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+        }
+        /* ../lib/standard/kernel.nit:232 */
          REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
        } else {
-        /* ./../lib/standard//collection//array.nit:245 */
+        /* ../lib/standard/collection/array.nit:280 */
          REGB0 = TAG_Bool(false);
          REGB2 = REGB0;
        }
        if (UNTAG_Bool(REGB2)) {
        } else {
-        nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+        nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
        }
-      /* ./../lib/standard//collection//array.nit:246 */
+      /* ../lib/standard/collection/array.nit:281 */
        fra.me.REG[6] = ATTR_standard___collection___array___Array____items(fra.me.REG[6]);
        REGB2 = TAG_Bool(fra.me.REG[6]==NIT_NULL);
        if (UNTAG_Bool(REGB2)) {
-        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
        }
-      /* ./../lib/standard//collection//array.nit:654 */
+      /* ../lib/standard/collection/array.nit:718 */
        fra.me.REG[6] = ((Nit_NativeArray)fra.me.REG[6])->val[UNTAG_Int(REGB1)];
-      /* ./../lib/standard//collection//array.nit:246 */
+      /* ../lib/standard/collection/array.nit:281 */
        goto label5;
        label5: while(0);
-      /* ./compiling//compiling_icode.nit:714 */
+      /* compiling/compiling_icode.nit:730 */
        fra.me.REG[5] = fra.me.REG[6];
      } else {
-      /* ./compiling//compiling_icode.nit:715 */
+      /* compiling/compiling_icode.nit:731 */
        if (!once_value_6) {
          if (!once_value_7) {
            fra.me.REG[6] = BOX_NativeString("unary -");
@@ -5315,7 +5514,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
          REGB1 = REGB2;
        }
        if (UNTAG_Bool(REGB1)) {
-        /* ./compiling//compiling_icode.nit:716 */
+        /* compiling/compiling_icode.nit:732 */
          REGB1 = TAG_Int(3);
          fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
          if (!once_value_8) {
@@ -5328,43 +5527,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
          fra.me.REG[7] = fra.me.REG[7];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
          REGB1 = TAG_Int(0);
-        /* ./../lib/standard//collection//array.nit:243 */
+        /* ../lib/standard/collection/array.nit:278 */
          fra.me.REG[7] = fra.me.REG[4];
-        /* ./../lib/standard//collection//array.nit:245 */
+        /* ../lib/standard/collection/array.nit:280 */
          REGB2 = TAG_Int(0);
-        /* ./../lib/standard//kernel.nit:216 */
+        REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+        if (UNTAG_Bool(REGB0)) {
+        } else {
+          nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+        }
+        /* ../lib/standard/kernel.nit:233 */
          REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-        /* ./../lib/standard//collection//array.nit:245 */
+        /* ../lib/standard/collection/array.nit:280 */
          if (UNTAG_Bool(REGB2)) {
            REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
            if (UNTAG_Bool(REGB2)) {
            } else {
-            nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+            nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
            }
            REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-          /* ./../lib/standard//kernel.nit:215 */
+          REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+          if (UNTAG_Bool(REGB0)) {
+          } else {
+            nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+          }
+          /* ../lib/standard/kernel.nit:232 */
            REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
          } else {
-          /* ./../lib/standard//collection//array.nit:245 */
+          /* ../lib/standard/collection/array.nit:280 */
            REGB0 = TAG_Bool(false);
            REGB2 = REGB0;
          }
          if (UNTAG_Bool(REGB2)) {
          } else {
-          nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+          nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
          }
-        /* ./../lib/standard//collection//array.nit:246 */
+        /* ../lib/standard/collection/array.nit:281 */
          fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
          REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
          if (UNTAG_Bool(REGB2)) {
-          nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+          nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
          }
-        /* ./../lib/standard//collection//array.nit:654 */
+        /* ../lib/standard/collection/array.nit:718 */
          fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-        /* ./../lib/standard//collection//array.nit:246 */
+        /* ../lib/standard/collection/array.nit:281 */
          goto label9;
          label9: while(0);
-        /* ./compiling//compiling_icode.nit:716 */
+        /* compiling/compiling_icode.nit:732 */
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
          if (!once_value_10) {
            fra.me.REG[7] = BOX_NativeString("))");
@@ -5378,7 +5587,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
          fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
          fra.me.REG[5] = fra.me.REG[6];
        } else {
-        /* ./compiling//compiling_icode.nit:717 */
+        /* compiling/compiling_icode.nit:733 */
          if (!once_value_11) {
            if (!once_value_12) {
              fra.me.REG[6] = BOX_NativeString("output");
@@ -5400,7 +5609,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            REGB1 = REGB2;
          }
          if (UNTAG_Bool(REGB1)) {
-          /* ./compiling//compiling_icode.nit:718 */
+          /* compiling/compiling_icode.nit:734 */
            REGB1 = TAG_Int(3);
            fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
            if (!once_value_13) {
@@ -5413,43 +5622,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            fra.me.REG[7] = fra.me.REG[7];
            CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
            REGB1 = TAG_Int(0);
-          /* ./../lib/standard//collection//array.nit:243 */
+          /* ../lib/standard/collection/array.nit:278 */
            fra.me.REG[7] = fra.me.REG[4];
-          /* ./../lib/standard//collection//array.nit:245 */
+          /* ../lib/standard/collection/array.nit:280 */
            REGB2 = TAG_Int(0);
-          /* ./../lib/standard//kernel.nit:216 */
+          REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+          if (UNTAG_Bool(REGB0)) {
+          } else {
+            nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+          }
+          /* ../lib/standard/kernel.nit:233 */
            REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-          /* ./../lib/standard//collection//array.nit:245 */
+          /* ../lib/standard/collection/array.nit:280 */
            if (UNTAG_Bool(REGB2)) {
              REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
              if (UNTAG_Bool(REGB2)) {
              } else {
-              nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+              nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
              }
              REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-            /* ./../lib/standard//kernel.nit:215 */
+            REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+            if (UNTAG_Bool(REGB0)) {
+            } else {
+              nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+            }
+            /* ../lib/standard/kernel.nit:232 */
              REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
            } else {
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              REGB0 = TAG_Bool(false);
              REGB2 = REGB0;
            }
            if (UNTAG_Bool(REGB2)) {
            } else {
-            nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+            nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
            }
-          /* ./../lib/standard//collection//array.nit:246 */
+          /* ../lib/standard/collection/array.nit:281 */
            fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
            REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
            if (UNTAG_Bool(REGB2)) {
-            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
            }
-          /* ./../lib/standard//collection//array.nit:654 */
+          /* ../lib/standard/collection/array.nit:718 */
            fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-          /* ./../lib/standard//collection//array.nit:246 */
+          /* ../lib/standard/collection/array.nit:281 */
            goto label14;
            label14: while(0);
-          /* ./compiling//compiling_icode.nit:718 */
+          /* compiling/compiling_icode.nit:734 */
            CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
            if (!once_value_15) {
              fra.me.REG[7] = BOX_NativeString("));");
@@ -5463,7 +5682,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
            fra.me.REG[5] = fra.me.REG[6];
          } else {
-          /* ./compiling//compiling_icode.nit:719 */
+          /* compiling/compiling_icode.nit:735 */
            if (!once_value_16) {
              if (!once_value_17) {
                fra.me.REG[6] = BOX_NativeString("ascii");
@@ -5485,7 +5704,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              REGB1 = REGB2;
            }
            if (UNTAG_Bool(REGB1)) {
-            /* ./compiling//compiling_icode.nit:720 */
+            /* compiling/compiling_icode.nit:736 */
              REGB1 = TAG_Int(3);
              fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
              if (!once_value_18) {
@@ -5498,43 +5717,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              fra.me.REG[7] = fra.me.REG[7];
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
              REGB1 = TAG_Int(0);
-            /* ./../lib/standard//collection//array.nit:243 */
+            /* ../lib/standard/collection/array.nit:278 */
              fra.me.REG[7] = fra.me.REG[4];
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              REGB2 = TAG_Int(0);
-            /* ./../lib/standard//kernel.nit:216 */
+            REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+            if (UNTAG_Bool(REGB0)) {
+            } else {
+              nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+            }
+            /* ../lib/standard/kernel.nit:233 */
              REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              if (UNTAG_Bool(REGB2)) {
                REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                if (UNTAG_Bool(REGB2)) {
                } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                }
                REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-              /* ./../lib/standard//kernel.nit:215 */
+              REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+              if (UNTAG_Bool(REGB0)) {
+              } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+              }
+              /* ../lib/standard/kernel.nit:232 */
                REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
              } else {
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                REGB0 = TAG_Bool(false);
                REGB2 = REGB0;
              }
              if (UNTAG_Bool(REGB2)) {
              } else {
-              nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+              nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
              }
-            /* ./../lib/standard//collection//array.nit:246 */
+            /* ../lib/standard/collection/array.nit:281 */
              fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
              REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
              if (UNTAG_Bool(REGB2)) {
-              nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+              nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
              }
-            /* ./../lib/standard//collection//array.nit:654 */
+            /* ../lib/standard/collection/array.nit:718 */
              fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-            /* ./../lib/standard//collection//array.nit:246 */
+            /* ../lib/standard/collection/array.nit:281 */
              goto label19;
              label19: while(0);
-            /* ./compiling//compiling_icode.nit:720 */
+            /* compiling/compiling_icode.nit:736 */
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
              if (!once_value_20) {
                fra.me.REG[7] = BOX_NativeString("))");
@@ -5548,7 +5777,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
              fra.me.REG[5] = fra.me.REG[6];
            } else {
-            /* ./compiling//compiling_icode.nit:721 */
+            /* compiling/compiling_icode.nit:737 */
              if (!once_value_21) {
                if (!once_value_22) {
                 fra.me.REG[6] = BOX_NativeString("succ");
@@ -5570,7 +5799,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                REGB1 = REGB2;
              }
              if (UNTAG_Bool(REGB1)) {
-              /* ./compiling//compiling_icode.nit:722 */
+              /* compiling/compiling_icode.nit:738 */
                REGB1 = TAG_Int(3);
                fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                if (!once_value_23) {
@@ -5583,43 +5812,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[7] = fra.me.REG[7];
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                REGB1 = TAG_Int(0);
-              /* ./../lib/standard//collection//array.nit:243 */
+              /* ../lib/standard/collection/array.nit:278 */
                fra.me.REG[7] = fra.me.REG[4];
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                REGB2 = TAG_Int(0);
-              /* ./../lib/standard//kernel.nit:216 */
+              REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+              if (UNTAG_Bool(REGB0)) {
+              } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+              }
+              /* ../lib/standard/kernel.nit:233 */
                REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                }
                if (UNTAG_Bool(REGB2)) {
                } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                }
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                }
-              /* ./../lib/standard//collection//array.nit:654 */
+              /* ../lib/standard/collection/array.nit:718 */
                fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                goto label24;
                label24: while(0);
-              /* ./compiling//compiling_icode.nit:722 */
+              /* compiling/compiling_icode.nit:738 */
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                if (!once_value_25) {
                 fra.me.REG[7] = BOX_NativeString(")+1)");
@@ -5633,7 +5872,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                fra.me.REG[5] = fra.me.REG[6];
              } else {
-              /* ./compiling//compiling_icode.nit:723 */
+              /* compiling/compiling_icode.nit:739 */
                if (!once_value_26) {
                 if (!once_value_27) {
                 fra.me.REG[6] = BOX_NativeString("prec");
@@ -5655,7 +5894,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                }
                if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:724 */
+               /* compiling/compiling_icode.nit:740 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_28) {
@@ -5668,43 +5907,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label29;
                 label29: while(0);
-               /* ./compiling//compiling_icode.nit:724 */
+               /* compiling/compiling_icode.nit:740 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_30) {
                 fra.me.REG[7] = BOX_NativeString(")-1)");
@@ -5718,7 +5967,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                } else {
-               /* ./compiling//compiling_icode.nit:725 */
+               /* compiling/compiling_icode.nit:741 */
                 if (!once_value_31) {
                 if (!once_value_32) {
                 fra.me.REG[6] = BOX_NativeString("to_f");
@@ -5740,7 +5989,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:726 */
+               /* compiling/compiling_icode.nit:742 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_33) {
@@ -5753,43 +6002,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
-               REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
+               REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label34;
                 label34: while(0);
-               /* ./compiling//compiling_icode.nit:726 */
+               /* compiling/compiling_icode.nit:742 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_35) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -5803,7 +6062,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:727 */
+               /* compiling/compiling_icode.nit:743 */
                 if (!once_value_36) {
                 if (!once_value_37) {
                 fra.me.REG[6] = BOX_NativeString("+");
@@ -5825,7 +6084,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:728 */
+               /* compiling/compiling_icode.nit:744 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_38) {
@@ -5838,43 +6097,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label39;
                 label39: while(0);
-               /* ./compiling//compiling_icode.nit:728 */
+               /* compiling/compiling_icode.nit:744 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_40) {
                 fra.me.REG[7] = BOX_NativeString(")+UNTAG_Int(");
@@ -5886,43 +6155,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label41;
                 label41: while(0);
-               /* ./compiling//compiling_icode.nit:728 */
+               /* compiling/compiling_icode.nit:744 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_42) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -5936,7 +6215,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:729 */
+               /* compiling/compiling_icode.nit:745 */
                 if (!once_value_43) {
                 if (!once_value_44) {
                 fra.me.REG[6] = BOX_NativeString("-");
@@ -5958,7 +6237,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:730 */
+               /* compiling/compiling_icode.nit:746 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_45) {
@@ -5971,43 +6250,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label46;
                 label46: while(0);
-               /* ./compiling//compiling_icode.nit:730 */
+               /* compiling/compiling_icode.nit:746 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_47) {
                 fra.me.REG[7] = BOX_NativeString(")-UNTAG_Int(");
@@ -6019,43 +6308,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label48;
                 label48: while(0);
-               /* ./compiling//compiling_icode.nit:730 */
+               /* compiling/compiling_icode.nit:746 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_49) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -6069,7 +6368,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:731 */
+               /* compiling/compiling_icode.nit:747 */
                 if (!once_value_50) {
                 if (!once_value_51) {
                 fra.me.REG[6] = BOX_NativeString("*");
@@ -6091,7 +6390,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:732 */
+               /* compiling/compiling_icode.nit:748 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_52) {
@@ -6104,43 +6403,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label53;
                 label53: while(0);
-               /* ./compiling//compiling_icode.nit:732 */
+               /* compiling/compiling_icode.nit:748 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_54) {
                 fra.me.REG[7] = BOX_NativeString(")*UNTAG_Int(");
@@ -6152,43 +6461,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label55;
                 label55: while(0);
-               /* ./compiling//compiling_icode.nit:732 */
+               /* compiling/compiling_icode.nit:748 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_56) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -6202,7 +6521,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:733 */
+               /* compiling/compiling_icode.nit:749 */
                 if (!once_value_57) {
                 if (!once_value_58) {
                 fra.me.REG[6] = BOX_NativeString("/");
@@ -6224,7 +6543,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:734 */
+               /* compiling/compiling_icode.nit:750 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_59) {
@@ -6237,43 +6556,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label60;
                 label60: while(0);
-               /* ./compiling//compiling_icode.nit:734 */
+               /* compiling/compiling_icode.nit:750 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_61) {
                 fra.me.REG[7] = BOX_NativeString(")/UNTAG_Int(");
@@ -6285,43 +6614,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label62;
                 label62: while(0);
-               /* ./compiling//compiling_icode.nit:734 */
+               /* compiling/compiling_icode.nit:750 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_63) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -6335,7 +6674,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:735 */
+               /* compiling/compiling_icode.nit:751 */
                 if (!once_value_64) {
                 if (!once_value_65) {
                 fra.me.REG[6] = BOX_NativeString("%");
@@ -6357,7 +6696,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:736 */
+               /* compiling/compiling_icode.nit:752 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_66) {
@@ -6370,43 +6709,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label67;
                 label67: while(0);
-               /* ./compiling//compiling_icode.nit:736 */
+               /* compiling/compiling_icode.nit:752 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_68) {
                 fra.me.REG[7] = BOX_NativeString(")%UNTAG_Int(");
@@ -6418,43 +6767,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label69;
                 label69: while(0);
-               /* ./compiling//compiling_icode.nit:736 */
+               /* compiling/compiling_icode.nit:752 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_70) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -6468,7 +6827,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:737 */
+               /* compiling/compiling_icode.nit:753 */
                 if (!once_value_71) {
                 if (!once_value_72) {
                 fra.me.REG[6] = BOX_NativeString("<");
@@ -6490,7 +6849,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:738 */
+               /* compiling/compiling_icode.nit:754 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_73) {
@@ -6503,43 +6862,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label74;
                 label74: while(0);
-               /* ./compiling//compiling_icode.nit:738 */
+               /* compiling/compiling_icode.nit:754 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_75) {
                 fra.me.REG[7] = BOX_NativeString(")<UNTAG_Int(");
@@ -6551,43 +6920,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label76;
                 label76: while(0);
-               /* ./compiling//compiling_icode.nit:738 */
+               /* compiling/compiling_icode.nit:754 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_77) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -6601,7 +6980,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:739 */
+               /* compiling/compiling_icode.nit:755 */
                 if (!once_value_78) {
                 if (!once_value_79) {
                 fra.me.REG[6] = BOX_NativeString(">");
@@ -6623,7 +7002,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:740 */
+               /* compiling/compiling_icode.nit:756 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_80) {
@@ -6636,43 +7015,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label81;
                 label81: while(0);
-               /* ./compiling//compiling_icode.nit:740 */
+               /* compiling/compiling_icode.nit:756 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_82) {
                 fra.me.REG[7] = BOX_NativeString(")>UNTAG_Int(");
@@ -6684,43 +7073,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label83;
                 label83: while(0);
-               /* ./compiling//compiling_icode.nit:740 */
+               /* compiling/compiling_icode.nit:756 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_84) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -6734,7 +7133,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:741 */
+               /* compiling/compiling_icode.nit:757 */
                 if (!once_value_85) {
                 if (!once_value_86) {
                 fra.me.REG[6] = BOX_NativeString("<=");
@@ -6756,7 +7155,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:742 */
+               /* compiling/compiling_icode.nit:758 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_87) {
@@ -6769,43 +7168,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label88;
                 label88: while(0);
-               /* ./compiling//compiling_icode.nit:742 */
+               /* compiling/compiling_icode.nit:758 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_89) {
                 fra.me.REG[7] = BOX_NativeString(")<=UNTAG_Int(");
@@ -6817,43 +7226,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label90;
                 label90: while(0);
-               /* ./compiling//compiling_icode.nit:742 */
+               /* compiling/compiling_icode.nit:758 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_91) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -6867,7 +7286,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:743 */
+               /* compiling/compiling_icode.nit:759 */
                 if (!once_value_92) {
                 if (!once_value_93) {
                 fra.me.REG[6] = BOX_NativeString(">=");
@@ -6889,7 +7308,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:744 */
+               /* compiling/compiling_icode.nit:760 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_94) {
@@ -6902,43 +7321,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label95;
                 label95: while(0);
-               /* ./compiling//compiling_icode.nit:744 */
+               /* compiling/compiling_icode.nit:760 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_96) {
                 fra.me.REG[7] = BOX_NativeString(")>=UNTAG_Int(");
@@ -6950,43 +7379,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label97;
                 label97: while(0);
-               /* ./compiling//compiling_icode.nit:744 */
+               /* compiling/compiling_icode.nit:760 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_98) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -7000,7 +7439,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:745 */
+               /* compiling/compiling_icode.nit:761 */
                 if (!once_value_99) {
                 if (!once_value_100) {
                 fra.me.REG[6] = BOX_NativeString("lshift");
@@ -7022,7 +7461,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:746 */
+               /* compiling/compiling_icode.nit:762 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_101) {
@@ -7035,43 +7474,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label102;
                 label102: while(0);
-               /* ./compiling//compiling_icode.nit:746 */
+               /* compiling/compiling_icode.nit:762 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_103) {
                 fra.me.REG[7] = BOX_NativeString(")<<UNTAG_Int(");
@@ -7083,43 +7532,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label104;
                 label104: while(0);
-               /* ./compiling//compiling_icode.nit:746 */
+               /* compiling/compiling_icode.nit:762 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_105) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -7133,7 +7592,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:747 */
+               /* compiling/compiling_icode.nit:763 */
                 if (!once_value_106) {
                 if (!once_value_107) {
                 fra.me.REG[6] = BOX_NativeString("rshift");
@@ -7155,7 +7614,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:748 */
+               /* compiling/compiling_icode.nit:764 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_108) {
@@ -7168,43 +7627,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label109;
                 label109: while(0);
-               /* ./compiling//compiling_icode.nit:748 */
+               /* compiling/compiling_icode.nit:764 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_110) {
                 fra.me.REG[7] = BOX_NativeString(")>>UNTAG_Int(");
@@ -7216,43 +7685,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label111;
                 label111: while(0);
-               /* ./compiling//compiling_icode.nit:748 */
+               /* compiling/compiling_icode.nit:764 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_112) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -7266,7 +7745,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:749 */
+               /* compiling/compiling_icode.nit:765 */
                 if (!once_value_113) {
                 if (!once_value_114) {
                 fra.me.REG[6] = BOX_NativeString("==");
@@ -7288,7 +7767,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:750 */
+               /* compiling/compiling_icode.nit:766 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_115) {
@@ -7301,43 +7780,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label116;
                 label116: while(0);
-               /* ./compiling//compiling_icode.nit:750 */
+               /* compiling/compiling_icode.nit:766 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_117) {
                 fra.me.REG[7] = BOX_NativeString(")==(");
@@ -7349,43 +7838,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label118;
                 label118: while(0);
-               /* ./compiling//compiling_icode.nit:750 */
+               /* compiling/compiling_icode.nit:766 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_119) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -7399,7 +7898,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:751 */
+               /* compiling/compiling_icode.nit:767 */
                 if (!once_value_120) {
                 if (!once_value_121) {
                 fra.me.REG[6] = BOX_NativeString("!=");
@@ -7421,7 +7920,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:752 */
+               /* compiling/compiling_icode.nit:768 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_122) {
@@ -7434,43 +7933,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label123;
                 label123: while(0);
-               /* ./compiling//compiling_icode.nit:752 */
+               /* compiling/compiling_icode.nit:768 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_124) {
                 fra.me.REG[7] = BOX_NativeString(")!=(");
@@ -7482,43 +7991,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label125;
                 label125: while(0);
-               /* ./compiling//compiling_icode.nit:752 */
+               /* compiling/compiling_icode.nit:768 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_126) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -7552,7 +8071,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
        }
      }
    } else {
-    /* ./compiling//compiling_icode.nit:754 */
+    /* compiling/compiling_icode.nit:770 */
      if (!once_value_127) {
        if (!once_value_128) {
          fra.me.REG[6] = BOX_NativeString("Float");
@@ -7574,7 +8093,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
        REGB1 = REGB2;
      }
      if (UNTAG_Bool(REGB1)) {
-      /* ./compiling//compiling_icode.nit:755 */
+      /* compiling/compiling_icode.nit:771 */
        if (!once_value_129) {
          if (!once_value_130) {
            fra.me.REG[6] = BOX_NativeString("object_id");
@@ -7596,7 +8115,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
          REGB1 = REGB2;
        }
        if (UNTAG_Bool(REGB1)) {
-        /* ./compiling//compiling_icode.nit:756 */
+        /* compiling/compiling_icode.nit:772 */
          REGB1 = TAG_Int(3);
          fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
          if (!once_value_131) {
@@ -7609,43 +8128,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
          fra.me.REG[7] = fra.me.REG[7];
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
          REGB1 = TAG_Int(0);
-        /* ./../lib/standard//collection//array.nit:243 */
+        /* ../lib/standard/collection/array.nit:278 */
          fra.me.REG[7] = fra.me.REG[4];
-        /* ./../lib/standard//collection//array.nit:245 */
+        /* ../lib/standard/collection/array.nit:280 */
          REGB2 = TAG_Int(0);
-        /* ./../lib/standard//kernel.nit:216 */
+        REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+        if (UNTAG_Bool(REGB0)) {
+        } else {
+          nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+        }
+        /* ../lib/standard/kernel.nit:233 */
          REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-        /* ./../lib/standard//collection//array.nit:245 */
+        /* ../lib/standard/collection/array.nit:280 */
          if (UNTAG_Bool(REGB2)) {
            REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
            if (UNTAG_Bool(REGB2)) {
            } else {
-            nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+            nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
            }
            REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-          /* ./../lib/standard//kernel.nit:215 */
+          REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+          if (UNTAG_Bool(REGB0)) {
+          } else {
+            nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+          }
+          /* ../lib/standard/kernel.nit:232 */
            REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
          } else {
-          /* ./../lib/standard//collection//array.nit:245 */
+          /* ../lib/standard/collection/array.nit:280 */
            REGB0 = TAG_Bool(false);
            REGB2 = REGB0;
          }
          if (UNTAG_Bool(REGB2)) {
          } else {
-          nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+          nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
          }
-        /* ./../lib/standard//collection//array.nit:246 */
+        /* ../lib/standard/collection/array.nit:281 */
          fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
          REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
          if (UNTAG_Bool(REGB2)) {
-          nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+          nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
          }
-        /* ./../lib/standard//collection//array.nit:654 */
+        /* ../lib/standard/collection/array.nit:718 */
          fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-        /* ./../lib/standard//collection//array.nit:246 */
+        /* ../lib/standard/collection/array.nit:281 */
          goto label132;
          label132: while(0);
-        /* ./compiling//compiling_icode.nit:756 */
+        /* compiling/compiling_icode.nit:772 */
          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
          if (!once_value_133) {
            fra.me.REG[7] = BOX_NativeString("))");
@@ -7659,7 +8188,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
          fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
          fra.me.REG[5] = fra.me.REG[6];
        } else {
-        /* ./compiling//compiling_icode.nit:757 */
+        /* compiling/compiling_icode.nit:773 */
          if (!once_value_134) {
            if (!once_value_135) {
              fra.me.REG[6] = BOX_NativeString("unary -");
@@ -7681,7 +8210,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            REGB1 = REGB2;
          }
          if (UNTAG_Bool(REGB1)) {
-          /* ./compiling//compiling_icode.nit:758 */
+          /* compiling/compiling_icode.nit:774 */
            REGB1 = TAG_Int(3);
            fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
            if (!once_value_136) {
@@ -7694,43 +8223,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            fra.me.REG[7] = fra.me.REG[7];
            CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
            REGB1 = TAG_Int(0);
-          /* ./../lib/standard//collection//array.nit:243 */
+          /* ../lib/standard/collection/array.nit:278 */
            fra.me.REG[7] = fra.me.REG[4];
-          /* ./../lib/standard//collection//array.nit:245 */
+          /* ../lib/standard/collection/array.nit:280 */
            REGB2 = TAG_Int(0);
-          /* ./../lib/standard//kernel.nit:216 */
+          REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+          if (UNTAG_Bool(REGB0)) {
+          } else {
+            nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+          }
+          /* ../lib/standard/kernel.nit:233 */
            REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-          /* ./../lib/standard//collection//array.nit:245 */
+          /* ../lib/standard/collection/array.nit:280 */
            if (UNTAG_Bool(REGB2)) {
              REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
              if (UNTAG_Bool(REGB2)) {
              } else {
-              nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+              nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
              }
              REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-            /* ./../lib/standard//kernel.nit:215 */
+            REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+            if (UNTAG_Bool(REGB0)) {
+            } else {
+              nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+            }
+            /* ../lib/standard/kernel.nit:232 */
              REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
            } else {
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              REGB0 = TAG_Bool(false);
              REGB2 = REGB0;
            }
            if (UNTAG_Bool(REGB2)) {
            } else {
-            nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+            nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
            }
-          /* ./../lib/standard//collection//array.nit:246 */
+          /* ../lib/standard/collection/array.nit:281 */
            fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
            REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
            if (UNTAG_Bool(REGB2)) {
-            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
            }
-          /* ./../lib/standard//collection//array.nit:654 */
+          /* ../lib/standard/collection/array.nit:718 */
            fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-          /* ./../lib/standard//collection//array.nit:246 */
+          /* ../lib/standard/collection/array.nit:281 */
            goto label137;
            label137: while(0);
-          /* ./compiling//compiling_icode.nit:758 */
+          /* compiling/compiling_icode.nit:774 */
            CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
            if (!once_value_138) {
              fra.me.REG[7] = BOX_NativeString("))");
@@ -7744,7 +8283,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
            fra.me.REG[5] = fra.me.REG[6];
          } else {
-          /* ./compiling//compiling_icode.nit:759 */
+          /* compiling/compiling_icode.nit:775 */
            if (!once_value_139) {
              if (!once_value_140) {
                fra.me.REG[6] = BOX_NativeString("output");
@@ -7766,7 +8305,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              REGB1 = REGB2;
            }
            if (UNTAG_Bool(REGB1)) {
-            /* ./compiling//compiling_icode.nit:760 */
+            /* compiling/compiling_icode.nit:776 */
              REGB1 = TAG_Int(3);
              fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
              if (!once_value_141) {
@@ -7779,43 +8318,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              fra.me.REG[7] = fra.me.REG[7];
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
              REGB1 = TAG_Int(0);
-            /* ./../lib/standard//collection//array.nit:243 */
+            /* ../lib/standard/collection/array.nit:278 */
              fra.me.REG[7] = fra.me.REG[4];
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              REGB2 = TAG_Int(0);
-            /* ./../lib/standard//kernel.nit:216 */
+            REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+            if (UNTAG_Bool(REGB0)) {
+            } else {
+              nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+            }
+            /* ../lib/standard/kernel.nit:233 */
              REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              if (UNTAG_Bool(REGB2)) {
                REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                if (UNTAG_Bool(REGB2)) {
                } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                }
                REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-              /* ./../lib/standard//kernel.nit:215 */
+              REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+              if (UNTAG_Bool(REGB0)) {
+              } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+              }
+              /* ../lib/standard/kernel.nit:232 */
                REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
              } else {
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                REGB0 = TAG_Bool(false);
                REGB2 = REGB0;
              }
              if (UNTAG_Bool(REGB2)) {
              } else {
-              nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+              nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
              }
-            /* ./../lib/standard//collection//array.nit:246 */
+            /* ../lib/standard/collection/array.nit:281 */
              fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
              REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
              if (UNTAG_Bool(REGB2)) {
-              nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+              nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
              }
-            /* ./../lib/standard//collection//array.nit:654 */
+            /* ../lib/standard/collection/array.nit:718 */
              fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-            /* ./../lib/standard//collection//array.nit:246 */
+            /* ../lib/standard/collection/array.nit:281 */
              goto label142;
              label142: while(0);
-            /* ./compiling//compiling_icode.nit:760 */
+            /* compiling/compiling_icode.nit:776 */
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
              if (!once_value_143) {
                fra.me.REG[7] = BOX_NativeString("));");
@@ -7829,7 +8378,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
              fra.me.REG[5] = fra.me.REG[6];
            } else {
-            /* ./compiling//compiling_icode.nit:761 */
+            /* compiling/compiling_icode.nit:777 */
              if (!once_value_144) {
                if (!once_value_145) {
                 fra.me.REG[6] = BOX_NativeString("to_i");
@@ -7851,7 +8400,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                REGB1 = REGB2;
              }
              if (UNTAG_Bool(REGB1)) {
-              /* ./compiling//compiling_icode.nit:762 */
+              /* compiling/compiling_icode.nit:778 */
                REGB1 = TAG_Int(3);
                fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                if (!once_value_146) {
@@ -7864,43 +8413,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[7] = fra.me.REG[7];
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                REGB1 = TAG_Int(0);
-              /* ./../lib/standard//collection//array.nit:243 */
+              /* ../lib/standard/collection/array.nit:278 */
                fra.me.REG[7] = fra.me.REG[4];
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                REGB2 = TAG_Int(0);
-              /* ./../lib/standard//kernel.nit:216 */
+              REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+              if (UNTAG_Bool(REGB0)) {
+              } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+              }
+              /* ../lib/standard/kernel.nit:233 */
                REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                }
                if (UNTAG_Bool(REGB2)) {
                } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                }
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                }
-              /* ./../lib/standard//collection//array.nit:654 */
+              /* ../lib/standard/collection/array.nit:718 */
                fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                goto label147;
                label147: while(0);
-              /* ./compiling//compiling_icode.nit:762 */
+              /* compiling/compiling_icode.nit:778 */
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                if (!once_value_148) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -7914,7 +8473,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                fra.me.REG[5] = fra.me.REG[6];
              } else {
-              /* ./compiling//compiling_icode.nit:763 */
+              /* compiling/compiling_icode.nit:779 */
                if (!once_value_149) {
                 if (!once_value_150) {
                 fra.me.REG[6] = BOX_NativeString("+");
@@ -7936,7 +8495,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                }
                if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:764 */
+               /* compiling/compiling_icode.nit:780 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_151) {
@@ -7949,43 +8508,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label152;
                 label152: while(0);
-               /* ./compiling//compiling_icode.nit:764 */
+               /* compiling/compiling_icode.nit:780 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_153) {
                 fra.me.REG[7] = BOX_NativeString(")+UNBOX_Float(");
@@ -7997,43 +8566,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label154;
                 label154: while(0);
-               /* ./compiling//compiling_icode.nit:764 */
+               /* compiling/compiling_icode.nit:780 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_155) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -8047,7 +8626,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                } else {
-               /* ./compiling//compiling_icode.nit:765 */
+               /* compiling/compiling_icode.nit:781 */
                 if (!once_value_156) {
                 if (!once_value_157) {
                 fra.me.REG[6] = BOX_NativeString("-");
@@ -8069,7 +8648,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:766 */
+               /* compiling/compiling_icode.nit:782 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_158) {
@@ -8082,43 +8661,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label159;
                 label159: while(0);
-               /* ./compiling//compiling_icode.nit:766 */
+               /* compiling/compiling_icode.nit:782 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_160) {
                 fra.me.REG[7] = BOX_NativeString(")-UNBOX_Float(");
@@ -8130,43 +8719,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label161;
                 label161: while(0);
-               /* ./compiling//compiling_icode.nit:766 */
+               /* compiling/compiling_icode.nit:782 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_162) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -8180,7 +8779,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:767 */
+               /* compiling/compiling_icode.nit:783 */
                 if (!once_value_163) {
                 if (!once_value_164) {
                 fra.me.REG[6] = BOX_NativeString("*");
@@ -8202,7 +8801,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:768 */
+               /* compiling/compiling_icode.nit:784 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_165) {
@@ -8215,43 +8814,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label166;
                 label166: while(0);
-               /* ./compiling//compiling_icode.nit:768 */
+               /* compiling/compiling_icode.nit:784 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_167) {
                 fra.me.REG[7] = BOX_NativeString(")*UNBOX_Float(");
@@ -8263,43 +8872,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label168;
                 label168: while(0);
-               /* ./compiling//compiling_icode.nit:768 */
+               /* compiling/compiling_icode.nit:784 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_169) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -8313,7 +8932,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:769 */
+               /* compiling/compiling_icode.nit:785 */
                 if (!once_value_170) {
                 if (!once_value_171) {
                 fra.me.REG[6] = BOX_NativeString("/");
@@ -8335,7 +8954,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:770 */
+               /* compiling/compiling_icode.nit:786 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_172) {
@@ -8348,43 +8967,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label173;
                 label173: while(0);
-               /* ./compiling//compiling_icode.nit:770 */
+               /* compiling/compiling_icode.nit:786 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_174) {
                 fra.me.REG[7] = BOX_NativeString(")/UNBOX_Float(");
@@ -8396,43 +9025,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label175;
                 label175: while(0);
-               /* ./compiling//compiling_icode.nit:770 */
+               /* compiling/compiling_icode.nit:786 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_176) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -8446,7 +9085,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:771 */
+               /* compiling/compiling_icode.nit:787 */
                 if (!once_value_177) {
                 if (!once_value_178) {
                 fra.me.REG[6] = BOX_NativeString("<");
@@ -8468,7 +9107,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:772 */
+               /* compiling/compiling_icode.nit:788 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_179) {
@@ -8481,43 +9120,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label180;
                 label180: while(0);
-               /* ./compiling//compiling_icode.nit:772 */
+               /* compiling/compiling_icode.nit:788 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_181) {
                 fra.me.REG[7] = BOX_NativeString(")<UNBOX_Float(");
@@ -8529,43 +9178,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label182;
                 label182: while(0);
-               /* ./compiling//compiling_icode.nit:772 */
+               /* compiling/compiling_icode.nit:788 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_183) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -8579,7 +9238,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:773 */
+               /* compiling/compiling_icode.nit:789 */
                 if (!once_value_184) {
                 if (!once_value_185) {
                 fra.me.REG[6] = BOX_NativeString(">");
@@ -8601,7 +9260,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:774 */
+               /* compiling/compiling_icode.nit:790 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_186) {
@@ -8614,43 +9273,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label187;
                 label187: while(0);
-               /* ./compiling//compiling_icode.nit:774 */
+               /* compiling/compiling_icode.nit:790 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_188) {
                 fra.me.REG[7] = BOX_NativeString(")>UNBOX_Float(");
@@ -8662,43 +9331,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label189;
                 label189: while(0);
-               /* ./compiling//compiling_icode.nit:774 */
+               /* compiling/compiling_icode.nit:790 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_190) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -8712,7 +9391,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:775 */
+               /* compiling/compiling_icode.nit:791 */
                 if (!once_value_191) {
                 if (!once_value_192) {
                 fra.me.REG[6] = BOX_NativeString("<=");
@@ -8734,7 +9413,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:776 */
+               /* compiling/compiling_icode.nit:792 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_193) {
@@ -8747,43 +9426,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label194;
                 label194: while(0);
-               /* ./compiling//compiling_icode.nit:776 */
+               /* compiling/compiling_icode.nit:792 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_195) {
                 fra.me.REG[7] = BOX_NativeString(")<=UNBOX_Float(");
@@ -8795,43 +9484,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label196;
                 label196: while(0);
-               /* ./compiling//compiling_icode.nit:776 */
+               /* compiling/compiling_icode.nit:792 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_197) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -8845,7 +9544,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:777 */
+               /* compiling/compiling_icode.nit:793 */
                 if (!once_value_198) {
                 if (!once_value_199) {
                 fra.me.REG[6] = BOX_NativeString(">=");
@@ -8867,7 +9566,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:778 */
+               /* compiling/compiling_icode.nit:794 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_200) {
@@ -8880,43 +9579,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label201;
                 label201: while(0);
-               /* ./compiling//compiling_icode.nit:778 */
+               /* compiling/compiling_icode.nit:794 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_202) {
                 fra.me.REG[7] = BOX_NativeString(")>=UNBOX_Float(");
@@ -8928,43 +9637,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label203;
                 label203: while(0);
-               /* ./compiling//compiling_icode.nit:778 */
+               /* compiling/compiling_icode.nit:794 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_204) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -8990,7 +9709,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
          }
        }
      } else {
-      /* ./compiling//compiling_icode.nit:780 */
+      /* compiling/compiling_icode.nit:796 */
        if (!once_value_205) {
          if (!once_value_206) {
            fra.me.REG[6] = BOX_NativeString("Char");
@@ -9012,7 +9731,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
          REGB1 = REGB2;
        }
        if (UNTAG_Bool(REGB1)) {
-        /* ./compiling//compiling_icode.nit:781 */
+        /* compiling/compiling_icode.nit:797 */
          if (!once_value_207) {
            if (!once_value_208) {
              fra.me.REG[6] = BOX_NativeString("object_id");
@@ -9034,7 +9753,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            REGB1 = REGB2;
          }
          if (UNTAG_Bool(REGB1)) {
-          /* ./compiling//compiling_icode.nit:782 */
+          /* compiling/compiling_icode.nit:798 */
            REGB1 = TAG_Int(3);
            fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
            if (!once_value_209) {
@@ -9047,43 +9766,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            fra.me.REG[7] = fra.me.REG[7];
            CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
            REGB1 = TAG_Int(0);
-          /* ./../lib/standard//collection//array.nit:243 */
+          /* ../lib/standard/collection/array.nit:278 */
            fra.me.REG[7] = fra.me.REG[4];
-          /* ./../lib/standard//collection//array.nit:245 */
+          /* ../lib/standard/collection/array.nit:280 */
            REGB2 = TAG_Int(0);
-          /* ./../lib/standard//kernel.nit:216 */
+          REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+          if (UNTAG_Bool(REGB0)) {
+          } else {
+            nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+          }
+          /* ../lib/standard/kernel.nit:233 */
            REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-          /* ./../lib/standard//collection//array.nit:245 */
+          /* ../lib/standard/collection/array.nit:280 */
            if (UNTAG_Bool(REGB2)) {
              REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
              if (UNTAG_Bool(REGB2)) {
              } else {
-              nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+              nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
              }
              REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-            /* ./../lib/standard//kernel.nit:215 */
+            REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+            if (UNTAG_Bool(REGB0)) {
+            } else {
+              nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+            }
+            /* ../lib/standard/kernel.nit:232 */
              REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
            } else {
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              REGB0 = TAG_Bool(false);
              REGB2 = REGB0;
            }
            if (UNTAG_Bool(REGB2)) {
            } else {
-            nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+            nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
            }
-          /* ./../lib/standard//collection//array.nit:246 */
+          /* ../lib/standard/collection/array.nit:281 */
            fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
            REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
            if (UNTAG_Bool(REGB2)) {
-            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
            }
-          /* ./../lib/standard//collection//array.nit:654 */
+          /* ../lib/standard/collection/array.nit:718 */
            fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-          /* ./../lib/standard//collection//array.nit:246 */
+          /* ../lib/standard/collection/array.nit:281 */
            goto label210;
            label210: while(0);
-          /* ./compiling//compiling_icode.nit:782 */
+          /* compiling/compiling_icode.nit:798 */
            CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
            if (!once_value_211) {
              fra.me.REG[7] = BOX_NativeString("))");
@@ -9097,7 +9826,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
            fra.me.REG[5] = fra.me.REG[6];
          } else {
-          /* ./compiling//compiling_icode.nit:783 */
+          /* compiling/compiling_icode.nit:799 */
            if (!once_value_212) {
              if (!once_value_213) {
                fra.me.REG[6] = BOX_NativeString("unary -");
@@ -9119,7 +9848,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              REGB1 = REGB2;
            }
            if (UNTAG_Bool(REGB1)) {
-            /* ./compiling//compiling_icode.nit:784 */
+            /* compiling/compiling_icode.nit:800 */
              REGB1 = TAG_Int(3);
              fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
              if (!once_value_214) {
@@ -9132,43 +9861,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              fra.me.REG[7] = fra.me.REG[7];
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
              REGB1 = TAG_Int(0);
-            /* ./../lib/standard//collection//array.nit:243 */
+            /* ../lib/standard/collection/array.nit:278 */
              fra.me.REG[7] = fra.me.REG[4];
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              REGB2 = TAG_Int(0);
-            /* ./../lib/standard//kernel.nit:216 */
+            REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+            if (UNTAG_Bool(REGB0)) {
+            } else {
+              nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+            }
+            /* ../lib/standard/kernel.nit:233 */
              REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              if (UNTAG_Bool(REGB2)) {
                REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                if (UNTAG_Bool(REGB2)) {
                } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                }
                REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-              /* ./../lib/standard//kernel.nit:215 */
+              REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+              if (UNTAG_Bool(REGB0)) {
+              } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+              }
+              /* ../lib/standard/kernel.nit:232 */
                REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
              } else {
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                REGB0 = TAG_Bool(false);
                REGB2 = REGB0;
              }
              if (UNTAG_Bool(REGB2)) {
              } else {
-              nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+              nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
              }
-            /* ./../lib/standard//collection//array.nit:246 */
+            /* ../lib/standard/collection/array.nit:281 */
              fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
              REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
              if (UNTAG_Bool(REGB2)) {
-              nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+              nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
              }
-            /* ./../lib/standard//collection//array.nit:654 */
+            /* ../lib/standard/collection/array.nit:718 */
              fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-            /* ./../lib/standard//collection//array.nit:246 */
+            /* ../lib/standard/collection/array.nit:281 */
              goto label215;
              label215: while(0);
-            /* ./compiling//compiling_icode.nit:784 */
+            /* compiling/compiling_icode.nit:800 */
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
              if (!once_value_216) {
                fra.me.REG[7] = BOX_NativeString("))");
@@ -9182,7 +9921,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
              fra.me.REG[5] = fra.me.REG[6];
            } else {
-            /* ./compiling//compiling_icode.nit:785 */
+            /* compiling/compiling_icode.nit:801 */
              if (!once_value_217) {
                if (!once_value_218) {
                 fra.me.REG[6] = BOX_NativeString("output");
@@ -9204,7 +9943,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                REGB1 = REGB2;
              }
              if (UNTAG_Bool(REGB1)) {
-              /* ./compiling//compiling_icode.nit:786 */
+              /* compiling/compiling_icode.nit:802 */
                REGB1 = TAG_Int(3);
                fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                if (!once_value_219) {
@@ -9217,43 +9956,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[7] = fra.me.REG[7];
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                REGB1 = TAG_Int(0);
-              /* ./../lib/standard//collection//array.nit:243 */
+              /* ../lib/standard/collection/array.nit:278 */
                fra.me.REG[7] = fra.me.REG[4];
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                REGB2 = TAG_Int(0);
-              /* ./../lib/standard//kernel.nit:216 */
+              REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+              if (UNTAG_Bool(REGB0)) {
+              } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+              }
+              /* ../lib/standard/kernel.nit:233 */
                REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                }
                if (UNTAG_Bool(REGB2)) {
                } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                }
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                }
-              /* ./../lib/standard//collection//array.nit:654 */
+              /* ../lib/standard/collection/array.nit:718 */
                fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                goto label220;
                label220: while(0);
-              /* ./compiling//compiling_icode.nit:786 */
+              /* compiling/compiling_icode.nit:802 */
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                if (!once_value_221) {
                 fra.me.REG[7] = BOX_NativeString("));");
@@ -9267,7 +10016,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                fra.me.REG[5] = fra.me.REG[6];
              } else {
-              /* ./compiling//compiling_icode.nit:787 */
+              /* compiling/compiling_icode.nit:803 */
                if (!once_value_222) {
                 if (!once_value_223) {
                 fra.me.REG[6] = BOX_NativeString("ascii");
@@ -9289,7 +10038,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                }
                if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:788 */
+               /* compiling/compiling_icode.nit:804 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_224) {
@@ -9302,43 +10051,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label225;
                 label225: while(0);
-               /* ./compiling//compiling_icode.nit:788 */
+               /* compiling/compiling_icode.nit:804 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_226) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -9352,7 +10111,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                } else {
-               /* ./compiling//compiling_icode.nit:789 */
+               /* compiling/compiling_icode.nit:805 */
                 if (!once_value_227) {
                 if (!once_value_228) {
                 fra.me.REG[6] = BOX_NativeString("succ");
@@ -9374,7 +10133,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:790 */
+               /* compiling/compiling_icode.nit:806 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_229) {
@@ -9387,43 +10146,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label230;
                 label230: while(0);
-               /* ./compiling//compiling_icode.nit:790 */
+               /* compiling/compiling_icode.nit:806 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_231) {
                 fra.me.REG[7] = BOX_NativeString(")+1)");
@@ -9437,7 +10206,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:791 */
+               /* compiling/compiling_icode.nit:807 */
                 if (!once_value_232) {
                 if (!once_value_233) {
                 fra.me.REG[6] = BOX_NativeString("prec");
@@ -9459,7 +10228,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:792 */
+               /* compiling/compiling_icode.nit:808 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_234) {
@@ -9472,43 +10241,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label235;
                 label235: while(0);
-               /* ./compiling//compiling_icode.nit:792 */
+               /* compiling/compiling_icode.nit:808 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_236) {
                 fra.me.REG[7] = BOX_NativeString(")-1)");
@@ -9522,7 +10301,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:793 */
+               /* compiling/compiling_icode.nit:809 */
                 if (!once_value_237) {
                 if (!once_value_238) {
                 fra.me.REG[6] = BOX_NativeString("to_i");
@@ -9544,7 +10323,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:794 */
+               /* compiling/compiling_icode.nit:810 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_239) {
@@ -9557,43 +10336,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label240;
                 label240: while(0);
-               /* ./compiling//compiling_icode.nit:794 */
+               /* compiling/compiling_icode.nit:810 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_241) {
                 fra.me.REG[7] = BOX_NativeString(")-'0')");
@@ -9607,7 +10396,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:795 */
+               /* compiling/compiling_icode.nit:811 */
                 if (!once_value_242) {
                 if (!once_value_243) {
                 fra.me.REG[6] = BOX_NativeString("+");
@@ -9629,7 +10418,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:796 */
+               /* compiling/compiling_icode.nit:812 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_244) {
@@ -9642,43 +10431,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label245;
                 label245: while(0);
-               /* ./compiling//compiling_icode.nit:796 */
+               /* compiling/compiling_icode.nit:812 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_246) {
                 fra.me.REG[7] = BOX_NativeString(")+UNTAG_Char(");
@@ -9690,43 +10489,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label247;
                 label247: while(0);
-               /* ./compiling//compiling_icode.nit:796 */
+               /* compiling/compiling_icode.nit:812 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_248) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -9740,7 +10549,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:797 */
+               /* compiling/compiling_icode.nit:813 */
                 if (!once_value_249) {
                 if (!once_value_250) {
                 fra.me.REG[6] = BOX_NativeString("-");
@@ -9762,7 +10571,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:798 */
+               /* compiling/compiling_icode.nit:814 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_251) {
@@ -9775,43 +10584,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label252;
                 label252: while(0);
-               /* ./compiling//compiling_icode.nit:798 */
+               /* compiling/compiling_icode.nit:814 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_253) {
                 fra.me.REG[7] = BOX_NativeString(")-UNTAG_Char(");
@@ -9823,43 +10642,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label254;
                 label254: while(0);
-               /* ./compiling//compiling_icode.nit:798 */
+               /* compiling/compiling_icode.nit:814 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_255) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -9873,7 +10702,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:799 */
+               /* compiling/compiling_icode.nit:815 */
                 if (!once_value_256) {
                 if (!once_value_257) {
                 fra.me.REG[6] = BOX_NativeString("*");
@@ -9895,7 +10724,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:800 */
+               /* compiling/compiling_icode.nit:816 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_258) {
@@ -9908,43 +10737,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label259;
                 label259: while(0);
-               /* ./compiling//compiling_icode.nit:800 */
+               /* compiling/compiling_icode.nit:816 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_260) {
                 fra.me.REG[7] = BOX_NativeString(")*UNTAG_Char(");
@@ -9956,43 +10795,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label261;
                 label261: while(0);
-               /* ./compiling//compiling_icode.nit:800 */
+               /* compiling/compiling_icode.nit:816 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_262) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -10006,7 +10855,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:801 */
+               /* compiling/compiling_icode.nit:817 */
                 if (!once_value_263) {
                 if (!once_value_264) {
                 fra.me.REG[6] = BOX_NativeString("/");
@@ -10028,7 +10877,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:802 */
+               /* compiling/compiling_icode.nit:818 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_265) {
@@ -10041,43 +10890,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label266;
                 label266: while(0);
-               /* ./compiling//compiling_icode.nit:802 */
+               /* compiling/compiling_icode.nit:818 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_267) {
                 fra.me.REG[7] = BOX_NativeString(")/UNTAG_Char(");
@@ -10089,43 +10948,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label268;
                 label268: while(0);
-               /* ./compiling//compiling_icode.nit:802 */
+               /* compiling/compiling_icode.nit:818 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_269) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -10139,7 +11008,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:803 */
+               /* compiling/compiling_icode.nit:819 */
                 if (!once_value_270) {
                 if (!once_value_271) {
                 fra.me.REG[6] = BOX_NativeString("%");
@@ -10161,7 +11030,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:804 */
+               /* compiling/compiling_icode.nit:820 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_272) {
@@ -10174,43 +11043,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
-               REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
+               REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
+               } else {
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label273;
                 label273: while(0);
-               /* ./compiling//compiling_icode.nit:804 */
+               /* compiling/compiling_icode.nit:820 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_274) {
                 fra.me.REG[7] = BOX_NativeString(")%UNTAG_Char(");
@@ -10222,43 +11101,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label275;
                 label275: while(0);
-               /* ./compiling//compiling_icode.nit:804 */
+               /* compiling/compiling_icode.nit:820 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_276) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -10272,7 +11161,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:805 */
+               /* compiling/compiling_icode.nit:821 */
                 if (!once_value_277) {
                 if (!once_value_278) {
                 fra.me.REG[6] = BOX_NativeString("<");
@@ -10294,7 +11183,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:806 */
+               /* compiling/compiling_icode.nit:822 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_279) {
@@ -10307,43 +11196,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label280;
                 label280: while(0);
-               /* ./compiling//compiling_icode.nit:806 */
+               /* compiling/compiling_icode.nit:822 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_281) {
                 fra.me.REG[7] = BOX_NativeString(")<UNTAG_Char(");
@@ -10355,43 +11254,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label282;
                 label282: while(0);
-               /* ./compiling//compiling_icode.nit:806 */
+               /* compiling/compiling_icode.nit:822 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_283) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -10405,7 +11314,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:807 */
+               /* compiling/compiling_icode.nit:823 */
                 if (!once_value_284) {
                 if (!once_value_285) {
                 fra.me.REG[6] = BOX_NativeString(">");
@@ -10427,7 +11336,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:808 */
+               /* compiling/compiling_icode.nit:824 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_286) {
@@ -10440,43 +11349,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label287;
                 label287: while(0);
-               /* ./compiling//compiling_icode.nit:808 */
+               /* compiling/compiling_icode.nit:824 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_288) {
                 fra.me.REG[7] = BOX_NativeString(")>UNTAG_Char(");
@@ -10488,43 +11407,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label289;
                 label289: while(0);
-               /* ./compiling//compiling_icode.nit:808 */
+               /* compiling/compiling_icode.nit:824 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_290) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -10538,7 +11467,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:809 */
+               /* compiling/compiling_icode.nit:825 */
                 if (!once_value_291) {
                 if (!once_value_292) {
                 fra.me.REG[6] = BOX_NativeString("<=");
@@ -10560,7 +11489,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:810 */
+               /* compiling/compiling_icode.nit:826 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_293) {
@@ -10573,43 +11502,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label294;
                 label294: while(0);
-               /* ./compiling//compiling_icode.nit:810 */
+               /* compiling/compiling_icode.nit:826 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_295) {
                 fra.me.REG[7] = BOX_NativeString(")<=UNTAG_Char(");
@@ -10621,43 +11560,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label296;
                 label296: while(0);
-               /* ./compiling//compiling_icode.nit:810 */
+               /* compiling/compiling_icode.nit:826 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_297) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -10671,7 +11620,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:811 */
+               /* compiling/compiling_icode.nit:827 */
                 if (!once_value_298) {
                 if (!once_value_299) {
                 fra.me.REG[6] = BOX_NativeString(">=");
@@ -10693,7 +11642,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:812 */
+               /* compiling/compiling_icode.nit:828 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_300) {
@@ -10706,43 +11655,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label301;
                 label301: while(0);
-               /* ./compiling//compiling_icode.nit:812 */
+               /* compiling/compiling_icode.nit:828 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_302) {
                 fra.me.REG[7] = BOX_NativeString(")>=UNTAG_Char(");
@@ -10754,43 +11713,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label303;
                 label303: while(0);
-               /* ./compiling//compiling_icode.nit:812 */
+               /* compiling/compiling_icode.nit:828 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_304) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -10804,7 +11773,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:813 */
+               /* compiling/compiling_icode.nit:829 */
                 if (!once_value_305) {
                 if (!once_value_306) {
                 fra.me.REG[6] = BOX_NativeString("==");
@@ -10826,7 +11795,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:814 */
+               /* compiling/compiling_icode.nit:830 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_307) {
@@ -10839,43 +11808,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label308;
                 label308: while(0);
-               /* ./compiling//compiling_icode.nit:814 */
+               /* compiling/compiling_icode.nit:830 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_309) {
                 fra.me.REG[7] = BOX_NativeString(")==(");
@@ -10887,43 +11866,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label310;
                 label310: while(0);
-               /* ./compiling//compiling_icode.nit:814 */
+               /* compiling/compiling_icode.nit:830 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_311) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -10937,7 +11926,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:815 */
+               /* compiling/compiling_icode.nit:831 */
                 if (!once_value_312) {
                 if (!once_value_313) {
                 fra.me.REG[6] = BOX_NativeString("!=");
@@ -10959,7 +11948,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:816 */
+               /* compiling/compiling_icode.nit:832 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_314) {
@@ -10972,43 +11961,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label315;
                 label315: while(0);
-               /* ./compiling//compiling_icode.nit:816 */
+               /* compiling/compiling_icode.nit:832 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_316) {
                 fra.me.REG[7] = BOX_NativeString(")!=(");
@@ -11020,43 +12019,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label317;
                 label317: while(0);
-               /* ./compiling//compiling_icode.nit:816 */
+               /* compiling/compiling_icode.nit:832 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_318) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -11088,7 +12097,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            }
          }
        } else {
-        /* ./compiling//compiling_icode.nit:818 */
+        /* compiling/compiling_icode.nit:834 */
          if (!once_value_319) {
            if (!once_value_320) {
              fra.me.REG[6] = BOX_NativeString("Bool");
@@ -11110,7 +12119,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
            REGB1 = REGB2;
          }
          if (UNTAG_Bool(REGB1)) {
-          /* ./compiling//compiling_icode.nit:819 */
+          /* compiling/compiling_icode.nit:835 */
            if (!once_value_321) {
              if (!once_value_322) {
                fra.me.REG[6] = BOX_NativeString("object_id");
@@ -11132,7 +12141,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              REGB1 = REGB2;
            }
            if (UNTAG_Bool(REGB1)) {
-            /* ./compiling//compiling_icode.nit:820 */
+            /* compiling/compiling_icode.nit:836 */
              REGB1 = TAG_Int(3);
              fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
              if (!once_value_323) {
@@ -11145,43 +12154,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              fra.me.REG[7] = fra.me.REG[7];
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
              REGB1 = TAG_Int(0);
-            /* ./../lib/standard//collection//array.nit:243 */
+            /* ../lib/standard/collection/array.nit:278 */
              fra.me.REG[7] = fra.me.REG[4];
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              REGB2 = TAG_Int(0);
-            /* ./../lib/standard//kernel.nit:216 */
+            REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+            if (UNTAG_Bool(REGB0)) {
+            } else {
+              nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+            }
+            /* ../lib/standard/kernel.nit:233 */
              REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-            /* ./../lib/standard//collection//array.nit:245 */
+            /* ../lib/standard/collection/array.nit:280 */
              if (UNTAG_Bool(REGB2)) {
                REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                if (UNTAG_Bool(REGB2)) {
                } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                }
                REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-              /* ./../lib/standard//kernel.nit:215 */
+              REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+              if (UNTAG_Bool(REGB0)) {
+              } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+              }
+              /* ../lib/standard/kernel.nit:232 */
                REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
              } else {
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                REGB0 = TAG_Bool(false);
                REGB2 = REGB0;
              }
              if (UNTAG_Bool(REGB2)) {
              } else {
-              nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+              nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
              }
-            /* ./../lib/standard//collection//array.nit:246 */
+            /* ../lib/standard/collection/array.nit:281 */
              fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
              REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
              if (UNTAG_Bool(REGB2)) {
-              nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+              nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
              }
-            /* ./../lib/standard//collection//array.nit:654 */
+            /* ../lib/standard/collection/array.nit:718 */
              fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-            /* ./../lib/standard//collection//array.nit:246 */
+            /* ../lib/standard/collection/array.nit:281 */
              goto label324;
              label324: while(0);
-            /* ./compiling//compiling_icode.nit:820 */
+            /* compiling/compiling_icode.nit:836 */
              CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
              if (!once_value_325) {
                fra.me.REG[7] = BOX_NativeString("))");
@@ -11195,7 +12214,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
              fra.me.REG[5] = fra.me.REG[6];
            } else {
-            /* ./compiling//compiling_icode.nit:821 */
+            /* compiling/compiling_icode.nit:837 */
              if (!once_value_326) {
                if (!once_value_327) {
                 fra.me.REG[6] = BOX_NativeString("unary -");
@@ -11217,7 +12236,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                REGB1 = REGB2;
              }
              if (UNTAG_Bool(REGB1)) {
-              /* ./compiling//compiling_icode.nit:822 */
+              /* compiling/compiling_icode.nit:838 */
                REGB1 = TAG_Int(3);
                fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                if (!once_value_328) {
@@ -11230,43 +12249,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[7] = fra.me.REG[7];
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                REGB1 = TAG_Int(0);
-              /* ./../lib/standard//collection//array.nit:243 */
+              /* ../lib/standard/collection/array.nit:278 */
                fra.me.REG[7] = fra.me.REG[4];
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                REGB2 = TAG_Int(0);
-              /* ./../lib/standard//kernel.nit:216 */
+              REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+              if (UNTAG_Bool(REGB0)) {
+              } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+              }
+              /* ../lib/standard/kernel.nit:233 */
                REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                }
                if (UNTAG_Bool(REGB2)) {
                } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                }
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                }
-              /* ./../lib/standard//collection//array.nit:654 */
+              /* ../lib/standard/collection/array.nit:718 */
                fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                goto label329;
                label329: while(0);
-              /* ./compiling//compiling_icode.nit:822 */
+              /* compiling/compiling_icode.nit:838 */
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                if (!once_value_330) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -11280,7 +12309,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                fra.me.REG[5] = fra.me.REG[6];
              } else {
-              /* ./compiling//compiling_icode.nit:823 */
+              /* compiling/compiling_icode.nit:839 */
                if (!once_value_331) {
                 if (!once_value_332) {
                 fra.me.REG[6] = BOX_NativeString("output");
@@ -11302,7 +12331,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                }
                if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:824 */
+               /* compiling/compiling_icode.nit:840 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_333) {
@@ -11315,43 +12344,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label334;
                 label334: while(0);
-               /* ./compiling//compiling_icode.nit:824 */
+               /* compiling/compiling_icode.nit:840 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_335) {
                 fra.me.REG[7] = BOX_NativeString(")?\"true\\n\":\"false\\n\");");
@@ -11365,7 +12404,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                } else {
-               /* ./compiling//compiling_icode.nit:825 */
+               /* compiling/compiling_icode.nit:841 */
                 if (!once_value_336) {
                 if (!once_value_337) {
                 fra.me.REG[6] = BOX_NativeString("ascii");
@@ -11387,7 +12426,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:826 */
+               /* compiling/compiling_icode.nit:842 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_338) {
@@ -11400,43 +12439,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label339;
                 label339: while(0);
-               /* ./compiling//compiling_icode.nit:826 */
+               /* compiling/compiling_icode.nit:842 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_340) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -11450,7 +12499,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:827 */
+               /* compiling/compiling_icode.nit:843 */
                 if (!once_value_341) {
                 if (!once_value_342) {
                 fra.me.REG[6] = BOX_NativeString("to_i");
@@ -11472,7 +12521,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:828 */
+               /* compiling/compiling_icode.nit:844 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_343) {
@@ -11485,43 +12534,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label344;
                 label344: while(0);
-               /* ./compiling//compiling_icode.nit:828 */
+               /* compiling/compiling_icode.nit:844 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_345) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -11535,7 +12594,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:829 */
+               /* compiling/compiling_icode.nit:845 */
                 if (!once_value_346) {
                 if (!once_value_347) {
                 fra.me.REG[6] = BOX_NativeString("==");
@@ -11557,7 +12616,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:830 */
+               /* compiling/compiling_icode.nit:846 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_348) {
@@ -11570,43 +12629,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label349;
                 label349: while(0);
-               /* ./compiling//compiling_icode.nit:830 */
+               /* compiling/compiling_icode.nit:846 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_350) {
                 fra.me.REG[7] = BOX_NativeString(")==(");
@@ -11618,43 +12687,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label351;
                 label351: while(0);
-               /* ./compiling//compiling_icode.nit:830 */
+               /* compiling/compiling_icode.nit:846 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_352) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -11668,7 +12747,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:831 */
+               /* compiling/compiling_icode.nit:847 */
                 if (!once_value_353) {
                 if (!once_value_354) {
                 fra.me.REG[6] = BOX_NativeString("!=");
@@ -11690,7 +12769,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:832 */
+               /* compiling/compiling_icode.nit:848 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_355) {
@@ -11703,43 +12782,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label356;
                 label356: while(0);
-               /* ./compiling//compiling_icode.nit:832 */
+               /* compiling/compiling_icode.nit:848 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_357) {
                 fra.me.REG[7] = BOX_NativeString(")!=(");
@@ -11751,43 +12840,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label358;
                 label358: while(0);
-               /* ./compiling//compiling_icode.nit:832 */
+               /* compiling/compiling_icode.nit:848 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_359) {
                 fra.me.REG[7] = BOX_NativeString("))");
@@ -11808,7 +12907,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              }
            }
          } else {
-          /* ./compiling//compiling_icode.nit:834 */
+          /* compiling/compiling_icode.nit:850 */
            if (!once_value_360) {
              if (!once_value_361) {
                fra.me.REG[6] = BOX_NativeString("NativeArray");
@@ -11830,7 +12929,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
              REGB1 = REGB2;
            }
            if (UNTAG_Bool(REGB1)) {
-            /* ./compiling//compiling_icode.nit:835 */
+            /* compiling/compiling_icode.nit:851 */
              if (!once_value_362) {
                if (!once_value_363) {
                 fra.me.REG[6] = BOX_NativeString("object_id");
@@ -11852,7 +12951,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                REGB1 = REGB2;
              }
              if (UNTAG_Bool(REGB1)) {
-              /* ./compiling//compiling_icode.nit:836 */
+              /* compiling/compiling_icode.nit:852 */
                REGB1 = TAG_Int(3);
                fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                if (!once_value_364) {
@@ -11865,43 +12964,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[7] = fra.me.REG[7];
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                REGB1 = TAG_Int(0);
-              /* ./../lib/standard//collection//array.nit:243 */
+              /* ../lib/standard/collection/array.nit:278 */
                fra.me.REG[7] = fra.me.REG[4];
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                REGB2 = TAG_Int(0);
-              /* ./../lib/standard//kernel.nit:216 */
+              REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+              if (UNTAG_Bool(REGB0)) {
+              } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+              }
+              /* ../lib/standard/kernel.nit:233 */
                REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-              /* ./../lib/standard//collection//array.nit:245 */
+              /* ../lib/standard/collection/array.nit:280 */
                if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                }
                if (UNTAG_Bool(REGB2)) {
                } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                }
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                }
-              /* ./../lib/standard//collection//array.nit:654 */
+              /* ../lib/standard/collection/array.nit:718 */
                fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-              /* ./../lib/standard//collection//array.nit:246 */
+              /* ../lib/standard/collection/array.nit:281 */
                goto label365;
                label365: while(0);
-              /* ./compiling//compiling_icode.nit:836 */
+              /* compiling/compiling_icode.nit:852 */
                CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                if (!once_value_366) {
                 fra.me.REG[7] = BOX_NativeString(")->object_id)");
@@ -11915,7 +13024,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                fra.me.REG[5] = fra.me.REG[6];
              } else {
-              /* ./compiling//compiling_icode.nit:837 */
+              /* compiling/compiling_icode.nit:853 */
                if (!once_value_367) {
                 if (!once_value_368) {
                 fra.me.REG[6] = BOX_NativeString("[]");
@@ -11937,7 +13046,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                }
                if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:838 */
+               /* compiling/compiling_icode.nit:854 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_369) {
@@ -11950,43 +13059,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label370;
                 label370: while(0);
-               /* ./compiling//compiling_icode.nit:838 */
+               /* compiling/compiling_icode.nit:854 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_371) {
                 fra.me.REG[7] = BOX_NativeString(")->val[UNTAG_Int(");
@@ -11998,43 +13117,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label372;
                 label372: while(0);
-               /* ./compiling//compiling_icode.nit:838 */
+               /* compiling/compiling_icode.nit:854 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_373) {
                 fra.me.REG[7] = BOX_NativeString(")]");
@@ -12048,7 +13177,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                } else {
-               /* ./compiling//compiling_icode.nit:839 */
+               /* compiling/compiling_icode.nit:855 */
                 if (!once_value_374) {
                 if (!once_value_375) {
                 fra.me.REG[6] = BOX_NativeString("[]=");
@@ -12070,7 +13199,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:840 */
+               /* compiling/compiling_icode.nit:856 */
                 REGB1 = TAG_Int(7);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_376) {
@@ -12083,43 +13212,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label377;
                 label377: while(0);
-               /* ./compiling//compiling_icode.nit:840 */
+               /* compiling/compiling_icode.nit:856 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_378) {
                 fra.me.REG[7] = BOX_NativeString(")->val[UNTAG_Int(");
@@ -12131,43 +13270,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label379;
                 label379: while(0);
-               /* ./compiling//compiling_icode.nit:840 */
+               /* compiling/compiling_icode.nit:856 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_380) {
                 fra.me.REG[7] = BOX_NativeString(")]=");
@@ -12179,43 +13328,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(2);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label381;
                 label381: while(0);
-               /* ./compiling//compiling_icode.nit:840 */
+               /* compiling/compiling_icode.nit:856 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_382) {
                 fra.me.REG[7] = BOX_NativeString("");
@@ -12229,7 +13388,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:841 */
+               /* compiling/compiling_icode.nit:857 */
                 if (!once_value_383) {
                 if (!once_value_384) {
                 fra.me.REG[6] = BOX_NativeString("copy_to");
@@ -12251,7 +13410,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:842 */
+               /* compiling/compiling_icode.nit:858 */
                 REGB1 = TAG_Int(7);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_385) {
@@ -12264,43 +13423,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label386;
                 label386: while(0);
-               /* ./compiling//compiling_icode.nit:842 */
+               /* compiling/compiling_icode.nit:858 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_387) {
                 fra.me.REG[7] = BOX_NativeString(")->val, ((Nit_NativeArray)");
@@ -12312,43 +13481,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label388;
                 label388: while(0);
-               /* ./compiling//compiling_icode.nit:842 */
+               /* compiling/compiling_icode.nit:858 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_389) {
                 fra.me.REG[7] = BOX_NativeString(")->val, UNTAG_Int(");
@@ -12360,43 +13539,53 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[7] = fra.me.REG[7];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(2);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[7] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
                 REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label390;
                 label390: while(0);
-               /* ./compiling//compiling_icode.nit:842 */
+               /* compiling/compiling_icode.nit:858 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_391) {
                 fra.me.REG[7] = BOX_NativeString(")*sizeof(val_t))");
@@ -12414,7 +13603,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                }
              }
            } else {
-            /* ./compiling//compiling_icode.nit:844 */
+            /* compiling/compiling_icode.nit:860 */
              if (!once_value_392) {
                if (!once_value_393) {
                 fra.me.REG[6] = BOX_NativeString("NativeString");
@@ -12436,7 +13625,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                REGB1 = REGB2;
              }
              if (UNTAG_Bool(REGB1)) {
-              /* ./compiling//compiling_icode.nit:845 */
+              /* compiling/compiling_icode.nit:861 */
                if (!once_value_394) {
                 if (!once_value_395) {
                 fra.me.REG[6] = BOX_NativeString("object_id");
@@ -12458,70 +13647,80 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                }
                if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:846 */
+               /* compiling/compiling_icode.nit:862 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_396) {
-               fra.me.REG[2] = BOX_NativeString("TAG_Int(UNBOX_NativeString(");
+               fra.me.REG[7] = BOX_NativeString("TAG_Int(UNBOX_NativeString(");
                 REGB1 = TAG_Int(27);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_396 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_396 = fra.me.REG[7];
                 register_static_object(&once_value_396);
-               } else fra.me.REG[2] = once_value_396;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_396;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label397;
                 label397: while(0);
-               /* ./compiling//compiling_icode.nit:846 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:862 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_398) {
-               fra.me.REG[2] = BOX_NativeString("))");
+               fra.me.REG[7] = BOX_NativeString("))");
                 REGB1 = TAG_Int(2);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_398 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_398 = fra.me.REG[7];
                 register_static_object(&once_value_398);
-               } else fra.me.REG[2] = once_value_398;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_398;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                } else {
-               /* ./compiling//compiling_icode.nit:847 */
+               /* compiling/compiling_icode.nit:863 */
                 if (!once_value_399) {
                 if (!once_value_400) {
                 fra.me.REG[6] = BOX_NativeString("atoi");
@@ -12543,70 +13742,80 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:848 */
+               /* compiling/compiling_icode.nit:864 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_401) {
-               fra.me.REG[2] = BOX_NativeString("TAG_Int(atoi(UNBOX_NativeString(");
+               fra.me.REG[7] = BOX_NativeString("TAG_Int(atoi(UNBOX_NativeString(");
                 REGB1 = TAG_Int(32);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_401 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_401 = fra.me.REG[7];
                 register_static_object(&once_value_401);
-               } else fra.me.REG[2] = once_value_401;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_401;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label402;
                 label402: while(0);
-               /* ./compiling//compiling_icode.nit:848 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:864 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_403) {
-               fra.me.REG[2] = BOX_NativeString(")))");
+               fra.me.REG[7] = BOX_NativeString(")))");
                 REGB1 = TAG_Int(3);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_403 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_403 = fra.me.REG[7];
                 register_static_object(&once_value_403);
-               } else fra.me.REG[2] = once_value_403;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_403;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:849 */
+               /* compiling/compiling_icode.nit:865 */
                 if (!once_value_404) {
                 if (!once_value_405) {
                 fra.me.REG[6] = BOX_NativeString("[]");
@@ -12628,118 +13837,138 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:850 */
+               /* compiling/compiling_icode.nit:866 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_406) {
-               fra.me.REG[2] = BOX_NativeString("TAG_Char(UNBOX_NativeString(");
+               fra.me.REG[7] = BOX_NativeString("TAG_Char(UNBOX_NativeString(");
                 REGB1 = TAG_Int(28);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_406 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_406 = fra.me.REG[7];
                 register_static_object(&once_value_406);
-               } else fra.me.REG[2] = once_value_406;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_406;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label407;
                 label407: while(0);
-               /* ./compiling//compiling_icode.nit:850 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:866 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_408) {
-               fra.me.REG[2] = BOX_NativeString(")[UNTAG_Int(");
+               fra.me.REG[7] = BOX_NativeString(")[UNTAG_Int(");
                 REGB1 = TAG_Int(12);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_408 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_408 = fra.me.REG[7];
                 register_static_object(&once_value_408);
-               } else fra.me.REG[2] = once_value_408;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_408;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label409;
                 label409: while(0);
-               /* ./compiling//compiling_icode.nit:850 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:866 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_410) {
-               fra.me.REG[2] = BOX_NativeString(")])");
+               fra.me.REG[7] = BOX_NativeString(")])");
                 REGB1 = TAG_Int(3);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_410 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_410 = fra.me.REG[7];
                 register_static_object(&once_value_410);
-               } else fra.me.REG[2] = once_value_410;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_410;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:851 */
+               /* compiling/compiling_icode.nit:867 */
                 if (!once_value_411) {
                 if (!once_value_412) {
                 fra.me.REG[6] = BOX_NativeString("[]=");
@@ -12761,166 +13990,196 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:852 */
+               /* compiling/compiling_icode.nit:868 */
                 REGB1 = TAG_Int(7);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_413) {
-               fra.me.REG[2] = BOX_NativeString("UNBOX_NativeString(");
+               fra.me.REG[7] = BOX_NativeString("UNBOX_NativeString(");
                 REGB1 = TAG_Int(19);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_413 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_413 = fra.me.REG[7];
                 register_static_object(&once_value_413);
-               } else fra.me.REG[2] = once_value_413;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_413;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label414;
                 label414: while(0);
-               /* ./compiling//compiling_icode.nit:852 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:868 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_415) {
-               fra.me.REG[2] = BOX_NativeString(")[UNTAG_Int(");
+               fra.me.REG[7] = BOX_NativeString(")[UNTAG_Int(");
                 REGB1 = TAG_Int(12);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_415 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_415 = fra.me.REG[7];
                 register_static_object(&once_value_415);
-               } else fra.me.REG[2] = once_value_415;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_415;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label416;
                 label416: while(0);
-               /* ./compiling//compiling_icode.nit:852 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:868 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_417) {
-               fra.me.REG[2] = BOX_NativeString(")]=UNTAG_Char(");
+               fra.me.REG[7] = BOX_NativeString(")]=UNTAG_Char(");
                 REGB1 = TAG_Int(14);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_417 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_417 = fra.me.REG[7];
                 register_static_object(&once_value_417);
-               } else fra.me.REG[2] = once_value_417;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_417;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(2);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label418;
                 label418: while(0);
-               /* ./compiling//compiling_icode.nit:852 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:868 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_419) {
-               fra.me.REG[2] = BOX_NativeString(");");
+               fra.me.REG[7] = BOX_NativeString(");");
                 REGB1 = TAG_Int(2);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_419 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_419 = fra.me.REG[7];
                 register_static_object(&once_value_419);
-               } else fra.me.REG[2] = once_value_419;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_419;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:853 */
+               /* compiling/compiling_icode.nit:869 */
                 if (!once_value_420) {
                 if (!once_value_421) {
                 fra.me.REG[6] = BOX_NativeString("copy_to");
@@ -12942,258 +14201,308 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:854 */
+               /* compiling/compiling_icode.nit:870 */
                 REGB1 = TAG_Int(11);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_422) {
-               fra.me.REG[2] = BOX_NativeString("(void)memcpy(UNBOX_NativeString(");
+               fra.me.REG[7] = BOX_NativeString("(void)memcpy(UNBOX_NativeString(");
                 REGB1 = TAG_Int(32);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_422 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_422 = fra.me.REG[7];
                 register_static_object(&once_value_422);
-               } else fra.me.REG[2] = once_value_422;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_422;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label423;
                 label423: while(0);
-               /* ./compiling//compiling_icode.nit:854 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:870 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_424) {
-               fra.me.REG[2] = BOX_NativeString(")+UNTAG_Int(");
+               fra.me.REG[7] = BOX_NativeString(")+UNTAG_Int(");
                 REGB1 = TAG_Int(12);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_424 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_424 = fra.me.REG[7];
                 register_static_object(&once_value_424);
-               } else fra.me.REG[2] = once_value_424;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_424;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(4);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label425;
                 label425: while(0);
-               /* ./compiling//compiling_icode.nit:854 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:870 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_426) {
-               fra.me.REG[2] = BOX_NativeString("), UNBOX_NativeString(");
+               fra.me.REG[7] = BOX_NativeString("), UNBOX_NativeString(");
                 REGB1 = TAG_Int(22);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_426 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_426 = fra.me.REG[7];
                 register_static_object(&once_value_426);
-               } else fra.me.REG[2] = once_value_426;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_426;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label427;
                 label427: while(0);
-               /* ./compiling//compiling_icode.nit:854 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:870 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_428) {
-               fra.me.REG[2] = BOX_NativeString(")+UNTAG_Int(");
+               fra.me.REG[7] = BOX_NativeString(")+UNTAG_Int(");
                 REGB1 = TAG_Int(12);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_428 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_428 = fra.me.REG[7];
                 register_static_object(&once_value_428);
-               } else fra.me.REG[2] = once_value_428;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_428;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(3);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label429;
                 label429: while(0);
-               /* ./compiling//compiling_icode.nit:854 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:870 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_430) {
-               fra.me.REG[2] = BOX_NativeString("), UNTAG_Int(");
+               fra.me.REG[7] = BOX_NativeString("), UNTAG_Int(");
                 REGB1 = TAG_Int(13);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_430 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_430 = fra.me.REG[7];
                 register_static_object(&once_value_430);
-               } else fra.me.REG[2] = once_value_430;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_430;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 REGB1 = TAG_Int(2);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[7] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[7]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[7] = ATTR_standard___collection___array___Array____items(fra.me.REG[7]);
+               REGB2 = TAG_Bool(fra.me.REG[7]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[7] = ((Nit_NativeArray)fra.me.REG[7])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label431;
                 label431: while(0);
-               /* ./compiling//compiling_icode.nit:854 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               /* compiling/compiling_icode.nit:870 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 if (!once_value_432) {
-               fra.me.REG[2] = BOX_NativeString("));");
+               fra.me.REG[7] = BOX_NativeString("));");
                 REGB1 = TAG_Int(3);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_432 = fra.me.REG[2];
+               fra.me.REG[7] = NEW_String_standard___string___String___with_native(fra.me.REG[7], REGB1);
+               once_value_432 = fra.me.REG[7];
                 register_static_object(&once_value_432);
-               } else fra.me.REG[2] = once_value_432;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               } else fra.me.REG[7] = once_value_432;
+               fra.me.REG[7] = fra.me.REG[7];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 }
@@ -13202,11 +14511,11 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 }
                }
              } else {
-              /* ./compiling//compiling_icode.nit:856 */
+              /* compiling/compiling_icode.nit:872 */
                if (!once_value_433) {
                 if (!once_value_434) {
-               fra.me.REG[6] = BOX_NativeString("object_id");
-               REGB1 = TAG_Int(9);
+               fra.me.REG[6] = BOX_NativeString("Sys");
+               REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
                 once_value_434 = fra.me.REG[6];
                 register_static_object(&once_value_434);
@@ -13217,90 +14526,156 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 register_static_object(&once_value_433);
                } else fra.me.REG[6] = once_value_433;
                fra.me.REG[6] = fra.me.REG[6];
-              REGB1 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[3],fra.me.REG[6]));
+              REGB1 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[2],fra.me.REG[6]));
                if (UNTAG_Bool(REGB1)) {
                } else {
-               REGB2 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[6]);
+               REGB2 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[6]);
                 REGB1 = REGB2;
                }
                if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:857 */
+               /* compiling/compiling_icode.nit:873 */
+               if (!once_value_435) {
+               if (!once_value_436) {
+               fra.me.REG[6] = BOX_NativeString("force_garbage_collection");
+               REGB1 = TAG_Int(24);
+               fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
+               once_value_436 = fra.me.REG[6];
+               register_static_object(&once_value_436);
+               } else fra.me.REG[6] = once_value_436;
+               fra.me.REG[6] = fra.me.REG[6];
+               fra.me.REG[6] = CALL_standard___symbol___String___to_symbol(fra.me.REG[6])(fra.me.REG[6]);
+               once_value_435 = fra.me.REG[6];
+               register_static_object(&once_value_435);
+               } else fra.me.REG[6] = once_value_435;
+               fra.me.REG[6] = fra.me.REG[6];
+               REGB1 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[3],fra.me.REG[6]));
+               if (UNTAG_Bool(REGB1)) {
+               } else {
+               REGB2 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[6]);
+               REGB1 = REGB2;
+               }
+               if (UNTAG_Bool(REGB1)) {
+               /* compiling/compiling_icode.nit:874 */
+               if (!once_value_437) {
+               fra.me.REG[6] = BOX_NativeString("Nit_gc_force_garbage_collection()");
+               REGB1 = TAG_Int(33);
+               fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
+               once_value_437 = fra.me.REG[6];
+               register_static_object(&once_value_437);
+               } else fra.me.REG[6] = once_value_437;
+               fra.me.REG[6] = fra.me.REG[6];
+               fra.me.REG[5] = fra.me.REG[6];
+               }
+              } else {
+               /* compiling/compiling_icode.nit:876 */
+               if (!once_value_438) {
+               if (!once_value_439) {
+               fra.me.REG[6] = BOX_NativeString("object_id");
+               REGB1 = TAG_Int(9);
+               fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
+               once_value_439 = fra.me.REG[6];
+               register_static_object(&once_value_439);
+               } else fra.me.REG[6] = once_value_439;
+               fra.me.REG[6] = fra.me.REG[6];
+               fra.me.REG[6] = CALL_standard___symbol___String___to_symbol(fra.me.REG[6])(fra.me.REG[6]);
+               once_value_438 = fra.me.REG[6];
+               register_static_object(&once_value_438);
+               } else fra.me.REG[6] = once_value_438;
+               fra.me.REG[6] = fra.me.REG[6];
+               REGB1 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[3],fra.me.REG[6]));
+               if (UNTAG_Bool(REGB1)) {
+               } else {
+               REGB2 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[6]);
+               REGB1 = REGB2;
+               }
+               if (UNTAG_Bool(REGB1)) {
+               /* compiling/compiling_icode.nit:877 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
-               if (!once_value_435) {
+               if (!once_value_440) {
                 fra.me.REG[2] = BOX_NativeString("TAG_Int((bigint)((obj_t)");
                 REGB1 = TAG_Int(24);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_435 = fra.me.REG[2];
-               register_static_object(&once_value_435);
-               } else fra.me.REG[2] = once_value_435;
+               once_value_440 = fra.me.REG[2];
+               register_static_object(&once_value_440);
+               } else fra.me.REG[2] = once_value_440;
                 fra.me.REG[2] = fra.me.REG[2];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
                 REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
-               goto label436;
-               label436: while(0);
-               /* ./compiling//compiling_icode.nit:857 */
+               /* ../lib/standard/collection/array.nit:281 */
+               goto label441;
+               label441: while(0);
+               /* compiling/compiling_icode.nit:877 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
-               if (!once_value_437) {
+               if (!once_value_442) {
                 fra.me.REG[2] = BOX_NativeString(")[1].object_id)");
                 REGB1 = TAG_Int(15);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_437 = fra.me.REG[2];
-               register_static_object(&once_value_437);
-               } else fra.me.REG[2] = once_value_437;
+               once_value_442 = fra.me.REG[2];
+               register_static_object(&once_value_442);
+               } else fra.me.REG[2] = once_value_442;
                 fra.me.REG[2] = fra.me.REG[2];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
-              } else {
-               /* ./compiling//compiling_icode.nit:858 */
-               if (!once_value_438) {
-               if (!once_value_439) {
+               } else {
+               /* compiling/compiling_icode.nit:878 */
+               if (!once_value_443) {
+               if (!once_value_444) {
                 fra.me.REG[6] = BOX_NativeString("sys");
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
-               once_value_439 = fra.me.REG[6];
-               register_static_object(&once_value_439);
-               } else fra.me.REG[6] = once_value_439;
+               once_value_444 = fra.me.REG[6];
+               register_static_object(&once_value_444);
+               } else fra.me.REG[6] = once_value_444;
                 fra.me.REG[6] = fra.me.REG[6];
                 fra.me.REG[6] = CALL_standard___symbol___String___to_symbol(fra.me.REG[6])(fra.me.REG[6]);
-               once_value_438 = fra.me.REG[6];
-               register_static_object(&once_value_438);
-               } else fra.me.REG[6] = once_value_438;
+               once_value_443 = fra.me.REG[6];
+               register_static_object(&once_value_443);
+               } else fra.me.REG[6] = once_value_443;
                 fra.me.REG[6] = fra.me.REG[6];
                 REGB1 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[3],fra.me.REG[6]));
                 if (UNTAG_Bool(REGB1)) {
@@ -13309,31 +14684,31 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:859 */
-               if (!once_value_440) {
+               /* compiling/compiling_icode.nit:879 */
+               if (!once_value_445) {
                 fra.me.REG[6] = BOX_NativeString("(G_sys)");
                 REGB1 = TAG_Int(7);
                 fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
-               once_value_440 = fra.me.REG[6];
-               register_static_object(&once_value_440);
-               } else fra.me.REG[6] = once_value_440;
+               once_value_445 = fra.me.REG[6];
+               register_static_object(&once_value_445);
+               } else fra.me.REG[6] = once_value_445;
                 fra.me.REG[6] = fra.me.REG[6];
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:860 */
-               if (!once_value_441) {
-               if (!once_value_442) {
+               /* compiling/compiling_icode.nit:880 */
+               if (!once_value_446) {
+               if (!once_value_447) {
                 fra.me.REG[6] = BOX_NativeString("is_same_type");
                 REGB1 = TAG_Int(12);
                 fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
-               once_value_442 = fra.me.REG[6];
-               register_static_object(&once_value_442);
-               } else fra.me.REG[6] = once_value_442;
+               once_value_447 = fra.me.REG[6];
+               register_static_object(&once_value_447);
+               } else fra.me.REG[6] = once_value_447;
                 fra.me.REG[6] = fra.me.REG[6];
                 fra.me.REG[6] = CALL_standard___symbol___String___to_symbol(fra.me.REG[6])(fra.me.REG[6]);
-               once_value_441 = fra.me.REG[6];
-               register_static_object(&once_value_441);
-               } else fra.me.REG[6] = once_value_441;
+               once_value_446 = fra.me.REG[6];
+               register_static_object(&once_value_446);
+               } else fra.me.REG[6] = once_value_446;
                 fra.me.REG[6] = fra.me.REG[6];
                 REGB1 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[3],fra.me.REG[6]));
                 if (UNTAG_Bool(REGB1)) {
@@ -13342,145 +14717,70 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:861 */
+               /* compiling/compiling_icode.nit:881 */
                 REGB1 = TAG_Int(5);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
-               if (!once_value_443) {
+               if (!once_value_448) {
                 fra.me.REG[2] = BOX_NativeString("TAG_Bool((VAL2VFT(");
                 REGB1 = TAG_Int(18);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_443 = fra.me.REG[2];
-               register_static_object(&once_value_443);
-               } else fra.me.REG[2] = once_value_443;
+               once_value_448 = fra.me.REG[2];
+               register_static_object(&once_value_448);
+               } else fra.me.REG[2] = once_value_448;
                 fra.me.REG[2] = fra.me.REG[2];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
-               REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
-               if (UNTAG_Bool(REGB2)) {
-               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
-               if (UNTAG_Bool(REGB2)) {
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
-               }
-               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
-               REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
-               } else {
-               /* ./../lib/standard//collection//array.nit:245 */
-               REGB0 = TAG_Bool(false);
-               REGB2 = REGB0;
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
                 }
-               if (UNTAG_Bool(REGB2)) {
-               } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
-               }
-               /* ./../lib/standard//collection//array.nit:246 */
-               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
-               if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
-               }
-               /* ./../lib/standard//collection//array.nit:654 */
-               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
-               goto label444;
-               label444: while(0);
-               /* ./compiling//compiling_icode.nit:861 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
-               if (!once_value_445) {
-               fra.me.REG[2] = BOX_NativeString(")==VAL2VFT(");
-               REGB1 = TAG_Int(11);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_445 = fra.me.REG[2];
-               register_static_object(&once_value_445);
-               } else fra.me.REG[2] = once_value_445;
-               fra.me.REG[2] = fra.me.REG[2];
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
-               REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
-               fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
-               REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
                 REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
-               goto label446;
-               label446: while(0);
-               /* ./compiling//compiling_icode.nit:861 */
-               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
-               if (!once_value_447) {
-               fra.me.REG[2] = BOX_NativeString(")))");
-               REGB1 = TAG_Int(3);
-               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
-               once_value_447 = fra.me.REG[2];
-               register_static_object(&once_value_447);
-               } else fra.me.REG[2] = once_value_447;
-               fra.me.REG[2] = fra.me.REG[2];
+               /* ../lib/standard/collection/array.nit:281 */
+               goto label449;
+               label449: while(0);
+               /* compiling/compiling_icode.nit:881 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
-               fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
-               fra.me.REG[5] = fra.me.REG[6];
-               } else {
-               /* ./compiling//compiling_icode.nit:862 */
-               if (!once_value_448) {
-               if (!once_value_449) {
-               fra.me.REG[6] = BOX_NativeString("exit");
-               REGB1 = TAG_Int(4);
-               fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
-               once_value_449 = fra.me.REG[6];
-               register_static_object(&once_value_449);
-               } else fra.me.REG[6] = once_value_449;
-               fra.me.REG[6] = fra.me.REG[6];
-               fra.me.REG[6] = CALL_standard___symbol___String___to_symbol(fra.me.REG[6])(fra.me.REG[6]);
-               once_value_448 = fra.me.REG[6];
-               register_static_object(&once_value_448);
-               } else fra.me.REG[6] = once_value_448;
-               fra.me.REG[6] = fra.me.REG[6];
-               REGB1 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[3],fra.me.REG[6]));
-               if (UNTAG_Bool(REGB1)) {
-               } else {
-               REGB2 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[6]);
-               REGB1 = REGB2;
-               }
-               if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:863 */
-               REGB1 = TAG_Int(3);
-               fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_450) {
-               fra.me.REG[2] = BOX_NativeString("exit(UNTAG_Int(");
-               REGB1 = TAG_Int(15);
+               fra.me.REG[2] = BOX_NativeString(")==VAL2VFT(");
+               REGB1 = TAG_Int(11);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
                 once_value_450 = fra.me.REG[2];
                 register_static_object(&once_value_450);
@@ -13488,46 +14788,56 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[2] = fra.me.REG[2];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
                 REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label451;
                 label451: while(0);
-               /* ./compiling//compiling_icode.nit:863 */
+               /* compiling/compiling_icode.nit:881 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 if (!once_value_452) {
-               fra.me.REG[2] = BOX_NativeString("));");
+               fra.me.REG[2] = BOX_NativeString(")))");
                 REGB1 = TAG_Int(3);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
                 once_value_452 = fra.me.REG[2];
@@ -13538,11 +14848,11 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:864 */
+               /* compiling/compiling_icode.nit:882 */
                 if (!once_value_453) {
                 if (!once_value_454) {
-               fra.me.REG[6] = BOX_NativeString("calloc_array");
-               REGB1 = TAG_Int(12);
+               fra.me.REG[6] = BOX_NativeString("exit");
+               REGB1 = TAG_Int(4);
                 fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
                 once_value_454 = fra.me.REG[6];
                 register_static_object(&once_value_454);
@@ -13560,12 +14870,12 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:865 */
+               /* compiling/compiling_icode.nit:883 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_455) {
-               fra.me.REG[2] = BOX_NativeString("NEW_NativeArray(UNTAG_Int(");
-               REGB1 = TAG_Int(26);
+               fra.me.REG[2] = BOX_NativeString("exit(UNTAG_Int(");
+               REGB1 = TAG_Int(15);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
                 once_value_455 = fra.me.REG[2];
                 register_static_object(&once_value_455);
@@ -13573,47 +14883,57 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[2] = fra.me.REG[2];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
                 REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label456;
                 label456: while(0);
-               /* ./compiling//compiling_icode.nit:865 */
+               /* compiling/compiling_icode.nit:883 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 if (!once_value_457) {
-               fra.me.REG[2] = BOX_NativeString("), sizeof(val_t))");
-               REGB1 = TAG_Int(17);
+               fra.me.REG[2] = BOX_NativeString("));");
+               REGB1 = TAG_Int(3);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
                 once_value_457 = fra.me.REG[2];
                 register_static_object(&once_value_457);
@@ -13623,11 +14943,11 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:866 */
+               /* compiling/compiling_icode.nit:884 */
                 if (!once_value_458) {
                 if (!once_value_459) {
-               fra.me.REG[6] = BOX_NativeString("calloc_string");
-               REGB1 = TAG_Int(13);
+               fra.me.REG[6] = BOX_NativeString("calloc_array");
+               REGB1 = TAG_Int(12);
                 fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
                 once_value_459 = fra.me.REG[6];
                 register_static_object(&once_value_459);
@@ -13645,12 +14965,12 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:867 */
+               /* compiling/compiling_icode.nit:885 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_460) {
-               fra.me.REG[2] = BOX_NativeString("BOX_NativeString((char*)raw_alloc((UNTAG_Int(");
-               REGB1 = TAG_Int(45);
+               fra.me.REG[2] = BOX_NativeString("NEW_NativeArray(UNTAG_Int(");
+               REGB1 = TAG_Int(26);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
                 once_value_460 = fra.me.REG[2];
                 register_static_object(&once_value_460);
@@ -13658,47 +14978,57 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[2] = fra.me.REG[2];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 REGB1 = TAG_Int(1);
-               /* ./../lib/standard//collection//array.nit:243 */
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
                 REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label461;
                 label461: while(0);
-               /* ./compiling//compiling_icode.nit:867 */
+               /* compiling/compiling_icode.nit:885 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 if (!once_value_462) {
-               fra.me.REG[2] = BOX_NativeString(") * sizeof(char))))");
-               REGB1 = TAG_Int(19);
+               fra.me.REG[2] = BOX_NativeString("), sizeof(val_t))");
+               REGB1 = TAG_Int(17);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
                 once_value_462 = fra.me.REG[2];
                 register_static_object(&once_value_462);
@@ -13708,11 +15038,11 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:869 */
+               /* compiling/compiling_icode.nit:886 */
                 if (!once_value_463) {
                 if (!once_value_464) {
-               fra.me.REG[6] = BOX_NativeString("output_class_name");
-               REGB1 = TAG_Int(17);
+               fra.me.REG[6] = BOX_NativeString("calloc_string");
+               REGB1 = TAG_Int(13);
                 fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
                 once_value_464 = fra.me.REG[6];
                 register_static_object(&once_value_464);
@@ -13730,60 +15060,70 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:870 */
+               /* compiling/compiling_icode.nit:887 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_465) {
-               fra.me.REG[2] = BOX_NativeString("printf(\"%s\\n\", VAL2VFT(");
-               REGB1 = TAG_Int(23);
+               fra.me.REG[2] = BOX_NativeString("BOX_NativeString((char*)raw_alloc((UNTAG_Int(");
+               REGB1 = TAG_Int(45);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
                 once_value_465 = fra.me.REG[2];
                 register_static_object(&once_value_465);
                 } else fra.me.REG[2] = once_value_465;
                 fra.me.REG[2] = fra.me.REG[2];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
-               REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:243 */
+               REGB1 = TAG_Int(1);
+               /* ../lib/standard/collection/array.nit:278 */
                 fra.me.REG[2] = fra.me.REG[4];
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
                 REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 goto label466;
                 label466: while(0);
-               /* ./compiling//compiling_icode.nit:870 */
+               /* compiling/compiling_icode.nit:887 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
                 if (!once_value_467) {
-               fra.me.REG[2] = BOX_NativeString(")[2].cname);");
-               REGB1 = TAG_Int(12);
+               fra.me.REG[2] = BOX_NativeString(") * sizeof(char))))");
+               REGB1 = TAG_Int(19);
                 fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
                 once_value_467 = fra.me.REG[2];
                 register_static_object(&once_value_467);
@@ -13793,10 +15133,10 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
                 fra.me.REG[5] = fra.me.REG[6];
                 } else {
-               /* ./compiling//compiling_icode.nit:872 */
+               /* compiling/compiling_icode.nit:889 */
                 if (!once_value_468) {
                 if (!once_value_469) {
-               fra.me.REG[6] = BOX_NativeString("native_class_name");
+               fra.me.REG[6] = BOX_NativeString("output_class_name");
                 REGB1 = TAG_Int(17);
                 fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
                 once_value_469 = fra.me.REG[6];
@@ -13815,62 +15155,167 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 REGB1 = REGB2;
                 }
                 if (UNTAG_Bool(REGB1)) {
-               /* ./compiling//compiling_icode.nit:873 */
+               /* compiling/compiling_icode.nit:890 */
                 REGB1 = TAG_Int(3);
                 fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
                 if (!once_value_470) {
+               fra.me.REG[2] = BOX_NativeString("printf(\"%s\\n\", VAL2VFT(");
+               REGB1 = TAG_Int(23);
+               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
+               once_value_470 = fra.me.REG[2];
+               register_static_object(&once_value_470);
+               } else fra.me.REG[2] = once_value_470;
+               fra.me.REG[2] = fra.me.REG[2];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               REGB1 = TAG_Int(0);
+               /* ../lib/standard/collection/array.nit:278 */
+               fra.me.REG[2] = fra.me.REG[4];
+               /* ../lib/standard/collection/array.nit:280 */
+               REGB2 = TAG_Int(0);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
+               REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
+               /* ../lib/standard/collection/array.nit:280 */
+               if (UNTAG_Bool(REGB2)) {
+               REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
+               if (UNTAG_Bool(REGB2)) {
+               } else {
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
+               }
+               REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
+               REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
+               } else {
+               /* ../lib/standard/collection/array.nit:280 */
+               REGB0 = TAG_Bool(false);
+               REGB2 = REGB0;
+               }
+               if (UNTAG_Bool(REGB2)) {
+               } else {
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
+               }
+               /* ../lib/standard/collection/array.nit:281 */
+               fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
+               REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+               if (UNTAG_Bool(REGB2)) {
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
+               }
+               /* ../lib/standard/collection/array.nit:718 */
+               fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
+               /* ../lib/standard/collection/array.nit:281 */
+               goto label471;
+               label471: while(0);
+               /* compiling/compiling_icode.nit:890 */
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               if (!once_value_472) {
+               fra.me.REG[2] = BOX_NativeString(")[2].cname);");
+               REGB1 = TAG_Int(12);
+               fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB1);
+               once_value_472 = fra.me.REG[2];
+               register_static_object(&once_value_472);
+               } else fra.me.REG[2] = once_value_472;
+               fra.me.REG[2] = fra.me.REG[2];
+               CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[2]);
+               fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
+               fra.me.REG[5] = fra.me.REG[6];
+               } else {
+               /* compiling/compiling_icode.nit:892 */
+               if (!once_value_473) {
+               if (!once_value_474) {
+               fra.me.REG[6] = BOX_NativeString("native_class_name");
+               REGB1 = TAG_Int(17);
+               fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
+               once_value_474 = fra.me.REG[6];
+               register_static_object(&once_value_474);
+               } else fra.me.REG[6] = once_value_474;
+               fra.me.REG[6] = fra.me.REG[6];
+               fra.me.REG[6] = CALL_standard___symbol___String___to_symbol(fra.me.REG[6])(fra.me.REG[6]);
+               once_value_473 = fra.me.REG[6];
+               register_static_object(&once_value_473);
+               } else fra.me.REG[6] = once_value_473;
+               fra.me.REG[6] = fra.me.REG[6];
+               REGB1 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[3],fra.me.REG[6]));
+               if (UNTAG_Bool(REGB1)) {
+               } else {
+               REGB2 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[6]);
+               REGB1 = REGB2;
+               }
+               if (UNTAG_Bool(REGB1)) {
+               /* compiling/compiling_icode.nit:893 */
+               REGB1 = TAG_Int(3);
+               fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
+               if (!once_value_475) {
                 fra.me.REG[3] = BOX_NativeString("BOX_NativeString(VAL2VFT(");
                 REGB1 = TAG_Int(25);
                 fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB1);
-               once_value_470 = fra.me.REG[3];
-               register_static_object(&once_value_470);
-               } else fra.me.REG[3] = once_value_470;
+               once_value_475 = fra.me.REG[3];
+               register_static_object(&once_value_475);
+               } else fra.me.REG[3] = once_value_475;
                 fra.me.REG[3] = fra.me.REG[3];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[3]);
                 REGB1 = TAG_Int(0);
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB2 = TAG_Int(0);
-               /* ./../lib/standard//kernel.nit:216 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:233 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB2));
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 if (UNTAG_Bool(REGB2)) {
                 REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[4])!=NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+               nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
                 }
                 REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[4]);
-               /* ./../lib/standard//kernel.nit:215 */
+               REGB0 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+               if (UNTAG_Bool(REGB0)) {
+               } else {
+               nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+               }
+               /* ../lib/standard/kernel.nit:232 */
                 REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
                 } else {
-               /* ./../lib/standard//collection//array.nit:245 */
+               /* ../lib/standard/collection/array.nit:280 */
                 REGB0 = TAG_Bool(false);
                 REGB2 = REGB0;
                 }
                 if (UNTAG_Bool(REGB2)) {
                 } else {
-               nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+               nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
                 }
-               /* ./../lib/standard//collection//array.nit:246 */
+               /* ../lib/standard/collection/array.nit:281 */
                 fra.me.REG[4] = ATTR_standard___collection___array___Array____items(fra.me.REG[4]);
                 REGB2 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
                 if (UNTAG_Bool(REGB2)) {
-               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+               nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
                 }
-               /* ./../lib/standard//collection//array.nit:654 */
+               /* ../lib/standard/collection/array.nit:718 */
                 fra.me.REG[4] = ((Nit_NativeArray)fra.me.REG[4])->val[UNTAG_Int(REGB1)];
-               /* ./../lib/standard//collection//array.nit:246 */
-               goto label471;
-               label471: while(0);
-               /* ./compiling//compiling_icode.nit:873 */
+               /* ../lib/standard/collection/array.nit:281 */
+               goto label476;
+               label476: while(0);
+               /* compiling/compiling_icode.nit:893 */
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[4]);
-               if (!once_value_472) {
+               if (!once_value_477) {
                 fra.me.REG[4] = BOX_NativeString(")[2].cname);");
                 REGB1 = TAG_Int(12);
                 fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB1);
-               once_value_472 = fra.me.REG[4];
-               register_static_object(&once_value_472);
-               } else fra.me.REG[4] = once_value_472;
+               once_value_477 = fra.me.REG[4];
+               register_static_object(&once_value_477);
+               } else fra.me.REG[4] = once_value_477;
                 fra.me.REG[4] = fra.me.REG[4];
                 CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[4]);
                 fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
@@ -13882,6 +15327,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
                 }
                 }
                 }
+               }
                }
              }
            }
@@ -13889,7 +15335,7 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
        }
      }
    }
-  /* ./compiling//compiling_icode.nit:876 */
+  /* compiling/compiling_icode.nit:896 */
    REGB1 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
    if (UNTAG_Bool(REGB1)) {
    } else {
@@ -13903,9 +15349,9 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
      }
    }
    if (UNTAG_Bool(REGB1)) {
-    /* ./compiling//compiling_icode.nit:877 */
+    /* compiling/compiling_icode.nit:897 */
      fra.me.REG[6] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
-    /* ./compiling//compiling_icode.nit:878 */
+    /* compiling/compiling_icode.nit:898 */
      REGB1 = TAG_Bool(fra.me.REG[6]==NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
      } else {
@@ -13922,81 +15368,81 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
      if (UNTAG_Bool(REGB1)) {
        REGB1 = TAG_Int(3);
        fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
-      if (!once_value_473) {
+      if (!once_value_478) {
          fra.me.REG[3] = BOX_NativeString("fprintf(stderr, \"");
          REGB1 = TAG_Int(17);
          fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB1);
-        once_value_473 = fra.me.REG[3];
-        register_static_object(&once_value_473);
-      } else fra.me.REG[3] = once_value_473;
+        once_value_478 = fra.me.REG[3];
+        register_static_object(&once_value_478);
+      } else fra.me.REG[3] = once_value_478;
        fra.me.REG[3] = fra.me.REG[3];
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
        REGB1 = TAG_Bool(fra.me.REG[6]==NIT_NULL);
        if (UNTAG_Bool(REGB1)) {
-        nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 878);
+        nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 898);
        }
        fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[6]);
-      if (!once_value_474) {
+      if (!once_value_479) {
          fra.me.REG[6] = BOX_NativeString(": \");");
          REGB1 = TAG_Int(5);
          fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
-        once_value_474 = fra.me.REG[6];
-        register_static_object(&once_value_474);
-      } else fra.me.REG[6] = once_value_474;
+        once_value_479 = fra.me.REG[6];
+        register_static_object(&once_value_479);
+      } else fra.me.REG[6] = once_value_479;
        fra.me.REG[6] = fra.me.REG[6];
        CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[6]);
        fra.me.REG[4] = CALL_standard___string___Object___to_s(fra.me.REG[4])(fra.me.REG[4]);
        CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
      }
-    /* ./compiling//compiling_icode.nit:879 */
+    /* compiling/compiling_icode.nit:899 */
      REGB1 = TAG_Int(3);
      fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
-    if (!once_value_475) {
+    if (!once_value_480) {
        fra.me.REG[6] = BOX_NativeString("fprintf(stderr, \"Fatal error: unknown intern method ");
        REGB1 = TAG_Int(52);
        fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
-      once_value_475 = fra.me.REG[6];
-      register_static_object(&once_value_475);
-    } else fra.me.REG[6] = once_value_475;
+      once_value_480 = fra.me.REG[6];
+      register_static_object(&once_value_480);
+    } else fra.me.REG[6] = once_value_480;
      fra.me.REG[6] = fra.me.REG[6];
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[6]);
      fra.me.REG[6] = CALL_icode___icode_base___INative___method(fra.me.REG[0])(fra.me.REG[0]);
      fra.me.REG[6] = CALL_metamodel___abstractmetamodel___MMLocalProperty___full_name(fra.me.REG[6])(fra.me.REG[6]);
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[6]);
-    if (!once_value_476) {
+    if (!once_value_481) {
        fra.me.REG[6] = BOX_NativeString(".\\n\");");
        REGB1 = TAG_Int(6);
        fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
-      once_value_476 = fra.me.REG[6];
-      register_static_object(&once_value_476);
-    } else fra.me.REG[6] = once_value_476;
+      once_value_481 = fra.me.REG[6];
+      register_static_object(&once_value_481);
+    } else fra.me.REG[6] = once_value_481;
      fra.me.REG[6] = fra.me.REG[6];
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[6]);
      fra.me.REG[4] = CALL_standard___string___Object___to_s(fra.me.REG[4])(fra.me.REG[4]);
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-    /* ./compiling//compiling_icode.nit:880 */
-    if (!once_value_477) {
+    /* compiling/compiling_icode.nit:900 */
+    if (!once_value_482) {
        fra.me.REG[4] = BOX_NativeString("nit_exit(1);");
        REGB1 = TAG_Int(12);
        fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB1);
-      once_value_477 = fra.me.REG[4];
-      register_static_object(&once_value_477);
-    } else fra.me.REG[4] = once_value_477;
+      once_value_482 = fra.me.REG[4];
+      register_static_object(&once_value_482);
+    } else fra.me.REG[4] = once_value_482;
      fra.me.REG[4] = fra.me.REG[4];
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-    /* ./compiling//compiling_icode.nit:881 */
-    if (!once_value_478) {
+    /* compiling/compiling_icode.nit:901 */
+    if (!once_value_483) {
        fra.me.REG[4] = BOX_NativeString("NIT_NULL");
        REGB1 = TAG_Int(8);
        fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB1);
-      once_value_478 = fra.me.REG[4];
-      register_static_object(&once_value_478);
-    } else fra.me.REG[4] = once_value_478;
+      once_value_483 = fra.me.REG[4];
+      register_static_object(&once_value_483);
+    } else fra.me.REG[4] = once_value_483;
      fra.me.REG[4] = fra.me.REG[4];
      fra.me.REG[5] = fra.me.REG[4];
    }
-  /* ./compiling//compiling_icode.nit:883 */
+  /* compiling/compiling_icode.nit:903 */
    fra.me.REG[4] = CALL_icode___icode_base___ICode___result(fra.me.REG[0])(fra.me.REG[0]);
    REGB1 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
    if (UNTAG_Bool(REGB1)) {
@@ -14011,25 +15457,25 @@ void compiling___compiling_icode___INative___compile_intern_method_to_c(val_t p0
      }
    }
    if (UNTAG_Bool(REGB1)) {
-    /* ./compiling//compiling_icode.nit:884 */
+    /* compiling/compiling_icode.nit:904 */
      fra.me.REG[4] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
      fra.me.REG[4] = CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
-    if (!once_value_479) {
+    if (!once_value_484) {
        fra.me.REG[6] = BOX_NativeString(";\n");
        REGB1 = TAG_Int(2);
        fra.me.REG[6] = NEW_String_standard___string___String___with_native(fra.me.REG[6], REGB1);
-      once_value_479 = fra.me.REG[6];
-      register_static_object(&once_value_479);
-    } else fra.me.REG[6] = once_value_479;
+      once_value_484 = fra.me.REG[6];
+      register_static_object(&once_value_484);
+    } else fra.me.REG[6] = once_value_484;
      fra.me.REG[6] = fra.me.REG[6];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[6]);
    } else {
-    /* ./compiling//compiling_icode.nit:885 */
+    /* compiling/compiling_icode.nit:905 */
      REGB1 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
      if (UNTAG_Bool(REGB1)) {
-      /* ./compiling//compiling_icode.nit:886 */
+      /* compiling/compiling_icode.nit:906 */
        fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-      /* ./compiling//compiling_icode.nit:887 */
+      /* compiling/compiling_icode.nit:907 */
        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
      }
    }
@@ -14044,21 +15490,22 @@ void compiling___compiling_icode___IIntValue___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_2; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 893;
+  fra.me.line = 913;
    fra.me.meth = LOCATE_compiling___compiling_icode___IIntValue___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:895 */
+  /* compiling/compiling_icode.nit:915 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:896 */
+  /* compiling/compiling_icode.nit:916 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:897 */
+  /* compiling/compiling_icode.nit:917 */
    if (!once_value_1) {
      fra.me.REG[2] = BOX_NativeString("TAG_Int(");
      REGB0 = TAG_Int(8);
@@ -14093,21 +15540,22 @@ void compiling___compiling_icode___IBoolValue___compile_to_c(val_t p0, val_t p1)
    static val_t once_value_4; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 902;
+  fra.me.line = 922;
    fra.me.meth = LOCATE_compiling___compiling_icode___IBoolValue___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:904 */
+  /* compiling/compiling_icode.nit:924 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:905 */
+  /* compiling/compiling_icode.nit:925 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:906 */
+  /* compiling/compiling_icode.nit:926 */
    if (!once_value_1) {
      fra.me.REG[2] = BOX_NativeString("TAG_Bool(");
      REGB0 = TAG_Int(9);
@@ -14117,7 +15565,7 @@ void compiling___compiling_icode___IBoolValue___compile_to_c(val_t p0, val_t p1)
    } else fra.me.REG[2] = once_value_1;
    fra.me.REG[2] = fra.me.REG[2];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:907 */
+  /* compiling/compiling_icode.nit:927 */
    REGB0 = CALL_icode___icode_base___IBoolValue___value(fra.me.REG[0])(fra.me.REG[0]);
    if (UNTAG_Bool(REGB0)) {
      if (!once_value_2) {
@@ -14140,7 +15588,7 @@ void compiling___compiling_icode___IBoolValue___compile_to_c(val_t p0, val_t p1)
      fra.me.REG[0] = fra.me.REG[0];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    }
-  /* ./compiling//compiling_icode.nit:908 */
+  /* compiling/compiling_icode.nit:928 */
    if (!once_value_4) {
      fra.me.REG[0] = BOX_NativeString(")");
      REGB0 = TAG_Int(1);
@@ -14161,21 +15609,22 @@ void compiling___compiling_icode___ICharValue___compile_to_c(val_t p0, val_t p1)
    static val_t once_value_2; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 913;
+  fra.me.line = 933;
    fra.me.meth = LOCATE_compiling___compiling_icode___ICharValue___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:915 */
+  /* compiling/compiling_icode.nit:935 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:916 */
+  /* compiling/compiling_icode.nit:936 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:917 */
+  /* compiling/compiling_icode.nit:937 */
    if (!once_value_1) {
      fra.me.REG[2] = BOX_NativeString("TAG_Char(");
      REGB0 = TAG_Int(9);
@@ -14207,21 +15656,22 @@ void compiling___compiling_icode___IFloatValue___compile_to_c(val_t p0, val_t p1
    static val_t once_value_2; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 922;
+  fra.me.line = 942;
    fra.me.meth = LOCATE_compiling___compiling_icode___IFloatValue___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:924 */
+  /* compiling/compiling_icode.nit:944 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:925 */
+  /* compiling/compiling_icode.nit:945 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:926 */
+  /* compiling/compiling_icode.nit:946 */
    if (!once_value_1) {
      fra.me.REG[2] = BOX_NativeString("BOX_Float(");
      REGB0 = TAG_Int(10);
@@ -14253,21 +15703,22 @@ void compiling___compiling_icode___IStringValue___compile_to_c(val_t p0, val_t p
    static val_t once_value_2; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 931;
+  fra.me.line = 951;
    fra.me.meth = LOCATE_compiling___compiling_icode___IStringValue___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:933 */
+  /* compiling/compiling_icode.nit:953 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:934 */
+  /* compiling/compiling_icode.nit:954 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:935 */
+  /* compiling/compiling_icode.nit:955 */
    if (!once_value_1) {
      fra.me.REG[2] = BOX_NativeString("BOX_NativeString(\"");
      REGB0 = TAG_Int(18);
@@ -14307,21 +15758,22 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_10; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 940;
+  fra.me.line = 960;
    fra.me.meth = LOCATE_compiling___compiling_icode___IAbort___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 3;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:942 */
+  /* compiling/compiling_icode.nit:962 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:943 */
+  /* compiling/compiling_icode.nit:963 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:944 */
+  /* compiling/compiling_icode.nit:964 */
    if (!once_value_1) {
      fra.me.REG[2] = BOX_NativeString("nit_abort(\"");
      REGB0 = TAG_Int(11);
@@ -14331,61 +15783,76 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[2] = once_value_1;
    fra.me.REG[2] = fra.me.REG[2];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:945 */
+  /* compiling/compiling_icode.nit:965 */
    fra.me.REG[2] = CALL_icode___icode_base___IAbort___texts(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = TAG_Int(0);
-  /* ./../lib/standard//collection//array.nit:245 */
+  /* ../lib/standard/collection/array.nit:280 */
    REGB1 = TAG_Int(0);
-  /* ./../lib/standard//kernel.nit:216 */
+  REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+  if (UNTAG_Bool(REGB2)) {
+  } else {
+    nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+  }
+  /* ../lib/standard/kernel.nit:233 */
    REGB1 = TAG_Bool(UNTAG_Int(REGB0)>=UNTAG_Int(REGB1));
-  /* ./../lib/standard//collection//array.nit:245 */
+  /* ../lib/standard/collection/array.nit:280 */
    if (UNTAG_Bool(REGB1)) {
      REGB1 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
      } else {
-      nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+      nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
      }
      REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-    /* ./../lib/standard//kernel.nit:215 */
+    REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+    if (UNTAG_Bool(REGB2)) {
+    } else {
+      nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+    }
+    /* ../lib/standard/kernel.nit:232 */
      REGB1 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
    } else {
-    /* ./../lib/standard//collection//array.nit:245 */
+    /* ../lib/standard/collection/array.nit:280 */
      REGB2 = TAG_Bool(false);
      REGB1 = REGB2;
    }
    if (UNTAG_Bool(REGB1)) {
    } else {
-    nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+    nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
    }
-  /* ./../lib/standard//collection//array.nit:246 */
+  /* ../lib/standard/collection/array.nit:281 */
    fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
    REGB1 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
    if (UNTAG_Bool(REGB1)) {
-    nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+    nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
    }
-  /* ./../lib/standard//collection//array.nit:654 */
+  /* ../lib/standard/collection/array.nit:718 */
    fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB0)];
-  /* ./../lib/standard//collection//array.nit:246 */
+  /* ../lib/standard/collection/array.nit:281 */
    goto label2;
    label2: while(0);
-  /* ./compiling//compiling_icode.nit:945 */
+  /* compiling/compiling_icode.nit:965 */
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:946 */
+  /* compiling/compiling_icode.nit:966 */
    fra.me.REG[2] = CALL_icode___icode_base___IAbort___texts(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./../lib/standard//collection//array.nit:23 */
+  /* ../lib/standard/collection/array.nit:24 */
    REGB0 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 23);
+    nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 24);
    }
    REGB0 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:946 */
+  /* compiling/compiling_icode.nit:966 */
    REGB1 = TAG_Int(1);
-  /* ./../lib/standard//kernel.nit:217 */
+  REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+  if (UNTAG_Bool(REGB2)) {
+  } else {
+    nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+  }
+  /* ../lib/standard/kernel.nit:234 */
    REGB1 = TAG_Bool(UNTAG_Int(REGB0)>UNTAG_Int(REGB1));
-  /* ./compiling//compiling_icode.nit:946 */
+  /* compiling/compiling_icode.nit:966 */
    if (UNTAG_Bool(REGB1)) {
-    /* ./compiling//compiling_icode.nit:947 */
+    /* compiling/compiling_icode.nit:967 */
      if (!once_value_3) {
        fra.me.REG[2] = BOX_NativeString("\", \"");
        REGB1 = TAG_Int(4);
@@ -14395,46 +15862,56 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
      } else fra.me.REG[2] = once_value_3;
      fra.me.REG[2] = fra.me.REG[2];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-    /* ./compiling//compiling_icode.nit:948 */
+    /* compiling/compiling_icode.nit:968 */
      fra.me.REG[2] = CALL_icode___icode_base___IAbort___texts(fra.me.REG[0])(fra.me.REG[0]);
      REGB1 = TAG_Int(1);
-    /* ./../lib/standard//collection//array.nit:245 */
+    /* ../lib/standard/collection/array.nit:280 */
      REGB0 = TAG_Int(0);
-    /* ./../lib/standard//kernel.nit:216 */
+    REGB2 = TAG_Bool(VAL_ISA(REGB0, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+    if (UNTAG_Bool(REGB2)) {
+    } else {
+      nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+    }
+    /* ../lib/standard/kernel.nit:233 */
      REGB0 = TAG_Bool(UNTAG_Int(REGB1)>=UNTAG_Int(REGB0));
-    /* ./../lib/standard//collection//array.nit:245 */
+    /* ../lib/standard/collection/array.nit:280 */
      if (UNTAG_Bool(REGB0)) {
        REGB0 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
        if (UNTAG_Bool(REGB0)) {
        } else {
-        nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 245);
+        nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
        }
        REGB0 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-      /* ./../lib/standard//kernel.nit:215 */
+      REGB2 = TAG_Bool(VAL_ISA(REGB0, VTCOLOR_standard___kernel___Comparable___OTHER(REGB1), VTID_standard___kernel___Comparable___OTHER(REGB1))) /*cast OTHER*/;
+      if (UNTAG_Bool(REGB2)) {
+      } else {
+        nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+      }
+      /* ../lib/standard/kernel.nit:232 */
        REGB0 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB0));
      } else {
-      /* ./../lib/standard//collection//array.nit:245 */
+      /* ../lib/standard/collection/array.nit:280 */
        REGB2 = TAG_Bool(false);
        REGB0 = REGB2;
      }
      if (UNTAG_Bool(REGB0)) {
      } else {
-      nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 245);
+      nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 280);
      }
-    /* ./../lib/standard//collection//array.nit:246 */
+    /* ../lib/standard/collection/array.nit:281 */
      fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
      REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 246);
+      nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
      }
-    /* ./../lib/standard//collection//array.nit:654 */
+    /* ../lib/standard/collection/array.nit:718 */
      fra.me.REG[2] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-    /* ./../lib/standard//collection//array.nit:246 */
+    /* ../lib/standard/collection/array.nit:281 */
      goto label4;
      label4: while(0);
-    /* ./compiling//compiling_icode.nit:948 */
+    /* compiling/compiling_icode.nit:968 */
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-    /* ./compiling//compiling_icode.nit:949 */
+    /* compiling/compiling_icode.nit:969 */
      if (!once_value_5) {
        fra.me.REG[2] = BOX_NativeString("\"");
        REGB1 = TAG_Int(1);
@@ -14445,7 +15922,7 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
      fra.me.REG[2] = fra.me.REG[2];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
    } else {
-    /* ./compiling//compiling_icode.nit:951 */
+    /* compiling/compiling_icode.nit:971 */
      if (!once_value_6) {
        fra.me.REG[2] = BOX_NativeString("\", NULL");
        REGB1 = TAG_Int(7);
@@ -14456,7 +15933,7 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
      fra.me.REG[2] = fra.me.REG[2];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
    }
-  /* ./compiling//compiling_icode.nit:953 */
+  /* compiling/compiling_icode.nit:973 */
    if (!once_value_7) {
      fra.me.REG[2] = BOX_NativeString(", LOCATE_");
      REGB1 = TAG_Int(9);
@@ -14466,13 +15943,13 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[2] = once_value_7;
    fra.me.REG[2] = fra.me.REG[2];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:954 */
+  /* compiling/compiling_icode.nit:974 */
    fra.me.REG[2] = CALL_icode___icode_base___IAbort___module_location(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[2] = CALL_compiling___compiling_base___MMModule___cname(fra.me.REG[2])(fra.me.REG[2]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:955 */
+  /* compiling/compiling_icode.nit:975 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:956 */
+  /* compiling/compiling_icode.nit:976 */
    REGB1 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
    if (UNTAG_Bool(REGB1)) {
    } else {
@@ -14487,7 +15964,7 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
    }
    REGB1 = TAG_Bool(!UNTAG_Bool(REGB1));
    if (UNTAG_Bool(REGB1)) {
-    /* ./compiling//compiling_icode.nit:957 */
+    /* compiling/compiling_icode.nit:977 */
      if (!once_value_8) {
        fra.me.REG[2] = BOX_NativeString(", ");
        REGB1 = TAG_Int(2);
@@ -14497,16 +15974,16 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
      } else fra.me.REG[2] = once_value_8;
      fra.me.REG[2] = fra.me.REG[2];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-    /* ./compiling//compiling_icode.nit:958 */
+    /* compiling/compiling_icode.nit:978 */
      REGB1 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
      if (UNTAG_Bool(REGB1)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 958);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 978);
      }
      REGB1 = CALL_location___Location___line_start(fra.me.REG[0])(fra.me.REG[0]);
      fra.me.REG[0] = CALL_standard___string___Object___to_s(REGB1)(REGB1);
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    } else {
-    /* ./compiling//compiling_icode.nit:960 */
+    /* compiling/compiling_icode.nit:980 */
      if (!once_value_9) {
        fra.me.REG[0] = BOX_NativeString(", 0");
        REGB1 = TAG_Int(3);
@@ -14517,7 +15994,7 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
      fra.me.REG[0] = fra.me.REG[0];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    }
-  /* ./compiling//compiling_icode.nit:962 */
+  /* compiling/compiling_icode.nit:982 */
    if (!once_value_10) {
      fra.me.REG[0] = BOX_NativeString(");\n");
      REGB1 = TAG_Int(3);
@@ -14531,7 +16008,7 @@ void compiling___compiling_icode___IAbort___compile_to_c(val_t p0, val_t p1){
    return;
  }
  void compiling___compiling_icode___IMove___compile_to_c(val_t p0, val_t p1){
-  struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[4];} fra;
    val_t REGB0;
    val_t REGB1;
    val_t tmp;
@@ -14539,72 +16016,76 @@ void compiling___compiling_icode___IMove___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 967;
+  fra.me.line = 987;
    fra.me.meth = LOCATE_compiling___compiling_icode___IMove___compile_to_c;
    fra.me.has_broke = 0;
-  fra.me.REG_size = 4;
+  fra.me.REG_size = 5;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
+  fra.me.REG[4] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:969 */
-  REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:987 */
+  fra.me.REG[2] = fra.me.REG[0];
+  /* compiling/compiling_icode.nit:989 */
+  REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[2])(fra.me.REG[2]);
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
      goto label1;
    }
-  /* ./compiling//compiling_icode.nit:970 */
-  fra.me.REG[2] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
-  fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:971 */
-  fra.me.REG[3] = CALL_icode___icode_base___ICode___result(fra.me.REG[0])(fra.me.REG[0]);
-  REGB0 = TAG_Bool((fra.me.REG[3]!=NIT_NULL) && VAL_ISA(fra.me.REG[3], COLOR_icode___icode_base___IRegister, ID_icode___icode_base___IRegister)) /*cast IRegister*/;
+  /* compiling/compiling_icode.nit:990 */
+  fra.me.REG[3] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[2])(fra.me.REG[2]);
+  fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:991 */
+  fra.me.REG[4] = CALL_icode___icode_base___ICode___result(fra.me.REG[2])(fra.me.REG[2]);
+  REGB0 = TAG_Bool((fra.me.REG[4]!=NIT_NULL) && VAL_ISA(fra.me.REG[4], COLOR_icode___icode_base___IRegister, ID_icode___icode_base___IRegister)) /*cast IRegister*/;
    if (UNTAG_Bool(REGB0)) {
    } else {
-    nit_abort("Cast failed", NULL, LOCATE_compiling___compiling_icode, 971);
+    nit_abort("Cast failed", NULL, LOCATE_compiling___compiling_icode, 991);
    }
-  fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:972 */
-  REGB0 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[2],fra.me.REG[3]));
+  fra.me.REG[4] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+  /* compiling/compiling_icode.nit:992 */
+  REGB0 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[3],fra.me.REG[4]));
    if (UNTAG_Bool(REGB0)) {
    } else {
-    REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
+    REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
      REGB0 = REGB1;
    }
    if (UNTAG_Bool(REGB0)) {
      goto label1;
    }
-  /* ./compiling//compiling_icode.nit:973 */
-  fra.me.REG[0] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
-  CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:974 */
+  /* compiling/compiling_icode.nit:993 */
+  fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[2])(fra.me.REG[2]);
+  CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
+  /* compiling/compiling_icode.nit:994 */
    fra.me.REG[1] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:975 */
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:976 */
+  /* compiling/compiling_icode.nit:995 */
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+  /* compiling/compiling_icode.nit:996 */
    if (!once_value_2) {
-    fra.me.REG[3] = BOX_NativeString(" = ");
+    fra.me.REG[4] = BOX_NativeString(" = ");
      REGB0 = TAG_Int(3);
-    fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-    once_value_2 = fra.me.REG[3];
+    fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+    once_value_2 = fra.me.REG[4];
      register_static_object(&once_value_2);
-  } else fra.me.REG[3] = once_value_2;
-  fra.me.REG[3] = fra.me.REG[3];
+  } else fra.me.REG[4] = once_value_2;
+  fra.me.REG[4] = fra.me.REG[4];
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+  /* compiling/compiling_icode.nit:997 */
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:977 */
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:978 */
+  /* compiling/compiling_icode.nit:998 */
    if (!once_value_3) {
-    fra.me.REG[2] = BOX_NativeString(";\n");
+    fra.me.REG[3] = BOX_NativeString(";\n");
      REGB0 = TAG_Int(2);
-    fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
-    once_value_3 = fra.me.REG[2];
+    fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+    once_value_3 = fra.me.REG[3];
      register_static_object(&once_value_3);
-  } else fra.me.REG[2] = once_value_3;
-  fra.me.REG[2] = fra.me.REG[2];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
+  } else fra.me.REG[3] = once_value_3;
+  fra.me.REG[3] = fra.me.REG[3];
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
    label1: while(0);
    stack_frame_head = fra.me.prev;
    return;
@@ -14617,33 +16098,34 @@ void compiling___compiling_icode___IAttrRead___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 983;
+  fra.me.line = 1003;
    fra.me.meth = LOCATE_compiling___compiling_icode___IAttrRead___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:985 */
+  /* compiling/compiling_icode.nit:1005 */
    REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
      goto label1;
    }
-  /* ./compiling//compiling_icode.nit:986 */
+  /* compiling/compiling_icode.nit:1006 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:987 */
+  /* compiling/compiling_icode.nit:1007 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:988 */
+  /* compiling/compiling_icode.nit:1008 */
    fra.me.REG[3] = CALL_icode___icode_base___IAttrRead___property(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[3])(fra.me.REG[3]);
    fra.me.REG[3] = CALL_compiling___compiling_base___MMGlobalProperty___attr_access(fra.me.REG[3])(fra.me.REG[3]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:989 */
+  /* compiling/compiling_icode.nit:1009 */
    if (!once_value_2) {
      fra.me.REG[3] = BOX_NativeString("(");
      REGB0 = TAG_Int(1);
@@ -14653,11 +16135,11 @@ void compiling___compiling_icode___IAttrRead___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[3] = once_value_2;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:990 */
+  /* compiling/compiling_icode.nit:1010 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:991 */
+  /* compiling/compiling_icode.nit:1011 */
    if (!once_value_3) {
      fra.me.REG[0] = BOX_NativeString(")");
      REGB0 = TAG_Int(1);
@@ -14680,28 +16162,29 @@ void compiling___compiling_icode___IAttrIsset___compile_to_c(val_t p0, val_t p1)
    static val_t once_value_4; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 996;
+  fra.me.line = 1016;
    fra.me.meth = LOCATE_compiling___compiling_icode___IAttrIsset___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:998 */
+  /* compiling/compiling_icode.nit:1018 */
    REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
      goto label1;
    }
-  /* ./compiling//compiling_icode.nit:999 */
+  /* compiling/compiling_icode.nit:1019 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1000 */
+  /* compiling/compiling_icode.nit:1020 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1001 */
+  /* compiling/compiling_icode.nit:1021 */
    if (!once_value_2) {
      fra.me.REG[3] = BOX_NativeString("TAG_Bool(");
      REGB0 = TAG_Int(9);
@@ -14711,12 +16194,12 @@ void compiling___compiling_icode___IAttrIsset___compile_to_c(val_t p0, val_t p1)
    } else fra.me.REG[3] = once_value_2;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1002 */
+  /* compiling/compiling_icode.nit:1022 */
    fra.me.REG[3] = CALL_icode___icode_base___IAttrIsset___property(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[3])(fra.me.REG[3]);
    fra.me.REG[3] = CALL_compiling___compiling_base___MMGlobalProperty___attr_access(fra.me.REG[3])(fra.me.REG[3]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1003 */
+  /* compiling/compiling_icode.nit:1023 */
    if (!once_value_3) {
      fra.me.REG[3] = BOX_NativeString("(");
      REGB0 = TAG_Int(1);
@@ -14726,11 +16209,11 @@ void compiling___compiling_icode___IAttrIsset___compile_to_c(val_t p0, val_t p1)
    } else fra.me.REG[3] = once_value_3;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1004 */
+  /* compiling/compiling_icode.nit:1024 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:1005 */
+  /* compiling/compiling_icode.nit:1025 */
    if (!once_value_4) {
      fra.me.REG[0] = BOX_NativeString(")!=NIT_NULL)");
      REGB0 = TAG_Int(12);
@@ -14753,27 +16236,28 @@ void compiling___compiling_icode___IAttrWrite___compile_to_c(val_t p0, val_t p1)
    static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 1010;
+  fra.me.line = 1030;
    fra.me.meth = LOCATE_compiling___compiling_icode___IAttrWrite___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:1012 */
+  /* compiling/compiling_icode.nit:1032 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1013 */
+  /* compiling/compiling_icode.nit:1033 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_instr(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1014 */
+  /* compiling/compiling_icode.nit:1034 */
    fra.me.REG[3] = CALL_icode___icode_base___IAttrWrite___property(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[3])(fra.me.REG[3]);
    fra.me.REG[3] = CALL_compiling___compiling_base___MMGlobalProperty___attr_access(fra.me.REG[3])(fra.me.REG[3]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1015 */
+  /* compiling/compiling_icode.nit:1035 */
    if (!once_value_1) {
      fra.me.REG[3] = BOX_NativeString("(");
      REGB0 = TAG_Int(1);
@@ -14783,11 +16267,11 @@ void compiling___compiling_icode___IAttrWrite___compile_to_c(val_t p0, val_t p1)
    } else fra.me.REG[3] = once_value_1;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1016 */
+  /* compiling/compiling_icode.nit:1036 */
    fra.me.REG[3] = CALL_icode___icode_base___ICode2___expr1(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1017 */
+  /* compiling/compiling_icode.nit:1037 */
    if (!once_value_2) {
      fra.me.REG[3] = BOX_NativeString(") = ");
      REGB0 = TAG_Int(4);
@@ -14797,11 +16281,11 @@ void compiling___compiling_icode___IAttrWrite___compile_to_c(val_t p0, val_t p1)
    } else fra.me.REG[3] = once_value_2;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1018 */
+  /* compiling/compiling_icode.nit:1038 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode2___expr2(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:1019 */
+  /* compiling/compiling_icode.nit:1039 */
    if (!once_value_3) {
      fra.me.REG[0] = BOX_NativeString(";\n");
      REGB0 = TAG_Int(2);
@@ -14825,17 +16309,27 @@ void compiling___compiling_icode___ITypeCheck___compile_to_c(val_t p0, val_t p1)
          static val_t once_value_5; /* Once value */
          static val_t once_value_6; /* Once value */
          static val_t once_value_7; /* Once value */
-  static val_t once_value_8; /* Once value */
-  static val_t once_value_9; /* Once value */
-  static val_t once_value_10; /* Once value */
-  static val_t once_value_11; /* Once value */
-  static val_t once_value_12; /* Once value */
+    static val_t once_value_8; /* Once value */
+    static val_t once_value_9; /* Once value */
+    static val_t once_value_10; /* Once value */
+    static val_t once_value_11; /* Once value */
+    static val_t once_value_12; /* Once value */
+    static val_t once_value_13; /* Once value */
+    static val_t once_value_14; /* Once value */
+    static val_t once_value_15; /* Once value */
+    static val_t once_value_16; /* Once value */
+    static val_t once_value_17; /* Once value */
+    static val_t once_value_18; /* Once value */
+    static val_t once_value_19; /* Once value */
+    static val_t once_value_20; /* Once value */
+    static val_t once_value_21; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 1024;
+  fra.me.line = 1044;
    fra.me.meth = LOCATE_compiling___compiling_icode___ITypeCheck___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 6;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -14844,25 +16338,21 @@ void compiling___compiling_icode___ITypeCheck___compile_to_c(val_t p0, val_t p1)
    fra.me.REG[5] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:1026 */
+  /* compiling/compiling_icode.nit:1046 */
    REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
      goto label1;
    }
-  /* ./compiling//compiling_icode.nit:1028 */
+  /* compiling/compiling_icode.nit:1047 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1029 */
-  fra.me.REG[2] = CALL_icode___icode_base___ITypeCheck___stype(fra.me.REG[0])(fra.me.REG[0]);
-  fra.me.REG[2] = CALL_metamodel___static_type___MMType___local_class(fra.me.REG[2])(fra.me.REG[2]);
-  fra.me.REG[2] = CALL_metamodel___abstractmetamodel___MMLocalClass___global(fra.me.REG[2])(fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1030 */
-  fra.me.REG[3] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
-  fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1031 */
-  fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1032 */
+  /* compiling/compiling_icode.nit:1048 */
+  fra.me.REG[2] = CALL_icode___icode_base___ICode2___expr2(fra.me.REG[0])(fra.me.REG[0]);
+  fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
+  /* compiling/compiling_icode.nit:1049 */
+  fra.me.REG[3] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
+  /* compiling/compiling_icode.nit:1050 */
    if (!once_value_2) {
      fra.me.REG[4] = BOX_NativeString("TAG_Bool(");
      REGB0 = TAG_Int(9);
@@ -14871,17 +16361,17 @@ void compiling___compiling_icode___ITypeCheck___compile_to_c(val_t p0, val_t p1)
      register_static_object(&once_value_2);
    } else fra.me.REG[4] = once_value_2;
    fra.me.REG[4] = fra.me.REG[4];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:1033 */
-  fra.me.REG[4] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+  /* compiling/compiling_icode.nit:1051 */
+  fra.me.REG[4] = CALL_icode___icode_base___ICode2___expr2(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[4] = CALL_icode___icode_base___IRegister___stype(fra.me.REG[4])(fra.me.REG[4]);
    REGB0 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[4])(fra.me.REG[4]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:1034 */
+    /* compiling/compiling_icode.nit:1052 */
      fra.me.REG[4] = CALL_icode___icode_base___ITypeCheck___stype(fra.me.REG[0])(fra.me.REG[0]);
      REGB0 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[4])(fra.me.REG[4]);
      if (UNTAG_Bool(REGB0)) {
-      /* ./compiling//compiling_icode.nit:1035 */
+      /* compiling/compiling_icode.nit:1053 */
        if (!once_value_3) {
          fra.me.REG[4] = BOX_NativeString("(");
          REGB0 = TAG_Int(1);
@@ -14890,10 +16380,10 @@ void compiling___compiling_icode___ITypeCheck___compile_to_c(val_t p0, val_t p1)
          register_static_object(&once_value_3);
        } else fra.me.REG[4] = once_value_3;
        fra.me.REG[4] = fra.me.REG[4];
-      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-      /* ./compiling//compiling_icode.nit:1036 */
-      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-      /* ./compiling//compiling_icode.nit:1037 */
+      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+      /* compiling/compiling_icode.nit:1054 */
+      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
+      /* compiling/compiling_icode.nit:1055 */
        if (!once_value_4) {
          fra.me.REG[4] = BOX_NativeString("==NIT_NULL) || ");
          REGB0 = TAG_Int(15);
@@ -14902,12 +16392,12 @@ void compiling___compiling_icode___ITypeCheck___compile_to_c(val_t p0, val_t p1)
          register_static_object(&once_value_4);
        } else fra.me.REG[4] = once_value_4;
        fra.me.REG[4] = fra.me.REG[4];
-      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
+      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
      } else {
-      /* ./compiling//compiling_icode.nit:1038 */
+      /* compiling/compiling_icode.nit:1056 */
        fra.me.REG[4] = CALL_icode___icode_base___ITypeCheck___stype(fra.me.REG[0])(fra.me.REG[0]);
        fra.me.REG[4] = CALL_metamodel___static_type___MMType___as_nullable(fra.me.REG[4])(fra.me.REG[4]);
-      fra.me.REG[5] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
+      fra.me.REG[5] = CALL_icode___icode_base___ICode2___expr2(fra.me.REG[0])(fra.me.REG[0]);
        fra.me.REG[5] = CALL_icode___icode_base___IRegister___stype(fra.me.REG[5])(fra.me.REG[5]);
        REGB0 = TAG_Bool(IS_EQUAL_OO(fra.me.REG[4],fra.me.REG[5]));
        if (UNTAG_Bool(REGB0)) {
@@ -14916,9 +16406,9 @@ void compiling___compiling_icode___ITypeCheck___compile_to_c(val_t p0, val_t p1)
          REGB0 = REGB1;
        }
        if (UNTAG_Bool(REGB0)) {
-        /* ./compiling//compiling_icode.nit:1039 */
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-        /* ./compiling//compiling_icode.nit:1040 */
+        /* compiling/compiling_icode.nit:1057 */
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
+        /* compiling/compiling_icode.nit:1058 */
          if (!once_value_5) {
            fra.me.REG[5] = BOX_NativeString("!=NIT_NULL)");
            REGB0 = TAG_Int(11);
@@ -14927,11 +16417,11 @@ void compiling___compiling_icode___ITypeCheck___compile_to_c(val_t p0, val_t p1)
            register_static_object(&once_value_5);
          } else fra.me.REG[5] = once_value_5;
          fra.me.REG[5] = fra.me.REG[5];
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
-        /* ./compiling//compiling_icode.nit:1041 */
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[5]);
+        /* compiling/compiling_icode.nit:1059 */
          goto label1;
        } else {
-        /* ./compiling//compiling_icode.nit:1043 */
+        /* compiling/compiling_icode.nit:1061 */
          if (!once_value_6) {
            fra.me.REG[5] = BOX_NativeString("(");
            REGB0 = TAG_Int(1);
@@ -14940,10 +16430,10 @@ void compiling___compiling_icode___ITypeCheck___compile_to_c(val_t p0, val_t p1)
            register_static_object(&once_value_6);
          } else fra.me.REG[5] = once_value_6;
          fra.me.REG[5] = fra.me.REG[5];
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
-        /* ./compiling//compiling_icode.nit:1044 */
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-        /* ./compiling//compiling_icode.nit:1045 */
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[5]);
+        /* compiling/compiling_icode.nit:1062 */
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
+        /* compiling/compiling_icode.nit:1063 */
          if (!once_value_7) {
            fra.me.REG[5] = BOX_NativeString("!=NIT_NULL) && ");
            REGB0 = TAG_Int(15);
@@ -14952,72 +16442,192 @@ void compiling___compiling_icode___ITypeCheck___compile_to_c(val_t p0, val_t p1)
            register_static_object(&once_value_7);
          } else fra.me.REG[5] = once_value_7;
          fra.me.REG[5] = fra.me.REG[5];
-        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
+        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[5]);
        }
      }
    }
-  /* ./compiling//compiling_icode.nit:1048 */
-  if (!once_value_8) {
-    fra.me.REG[5] = BOX_NativeString("VAL_ISA(");
-    REGB0 = TAG_Int(8);
-    fra.me.REG[5] = NEW_String_standard___string___String___with_native(fra.me.REG[5], REGB0);
-    once_value_8 = fra.me.REG[5];
-    register_static_object(&once_value_8);
-  } else fra.me.REG[5] = once_value_8;
-  fra.me.REG[5] = fra.me.REG[5];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
-  /* ./compiling//compiling_icode.nit:1049 */
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1050 */
-  if (!once_value_9) {
-    fra.me.REG[3] = BOX_NativeString(", ");
-    REGB0 = TAG_Int(2);
-    fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-    once_value_9 = fra.me.REG[3];
-    register_static_object(&once_value_9);
-  } else fra.me.REG[3] = once_value_9;
-  fra.me.REG[3] = fra.me.REG[3];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1051 */
-  fra.me.REG[3] = CALL_compiling___compiling_base___MMGlobalClass___color_id(fra.me.REG[2])(fra.me.REG[2]);
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1052 */
-  if (!once_value_10) {
-    fra.me.REG[3] = BOX_NativeString(", ");
-    REGB0 = TAG_Int(2);
-    fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
-    once_value_10 = fra.me.REG[3];
-    register_static_object(&once_value_10);
-  } else fra.me.REG[3] = once_value_10;
-  fra.me.REG[3] = fra.me.REG[3];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1053 */
-  fra.me.REG[2] = CALL_compiling___compiling_base___MMGlobalClass___id_id(fra.me.REG[2])(fra.me.REG[2]);
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1054 */
-  if (!once_value_11) {
-    fra.me.REG[2] = BOX_NativeString(")) /*cast ");
-    REGB0 = TAG_Int(10);
-    fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
-    once_value_11 = fra.me.REG[2];
-    register_static_object(&once_value_11);
-  } else fra.me.REG[2] = once_value_11;
-  fra.me.REG[2] = fra.me.REG[2];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1055 */
-  fra.me.REG[0] = CALL_icode___icode_base___ITypeCheck___stype(fra.me.REG[0])(fra.me.REG[0]);
-  fra.me.REG[0] = CALL_standard___string___Object___to_s(fra.me.REG[0])(fra.me.REG[0]);
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:1056 */
-  if (!once_value_12) {
-    fra.me.REG[0] = BOX_NativeString("*/");
-    REGB0 = TAG_Int(2);
-    fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
-    once_value_12 = fra.me.REG[0];
-    register_static_object(&once_value_12);
-  } else fra.me.REG[0] = once_value_12;
-  fra.me.REG[0] = fra.me.REG[0];
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:1067 */
+  fra.me.REG[5] = CALL_icode___icode_base___ITypeCheck___stype(fra.me.REG[0])(fra.me.REG[0]);
+  /* compiling/compiling_icode.nit:1068 */
+  REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[5], COLOR_metamodel___virtualtype___MMVirtualType, ID_metamodel___virtualtype___MMVirtualType)) /*cast MMVirtualType*/;
+  if (UNTAG_Bool(REGB0)) {
+    /* compiling/compiling_icode.nit:1069 */
+    fra.me.REG[0] = CALL_icode___icode_base___ICode2___expr1(fra.me.REG[0])(fra.me.REG[0]);
+    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1070 */
+    fra.me.REG[1] = CALL_metamodel___virtualtype___MMVirtualType___property(fra.me.REG[5])(fra.me.REG[5]);
+    fra.me.REG[1] = CALL_metamodel___abstractmetamodel___MMLocalProperty___global(fra.me.REG[1])(fra.me.REG[1]);
+    /* compiling/compiling_icode.nit:1071 */
+    if (!once_value_8) {
+      fra.me.REG[4] = BOX_NativeString("VAL_ISA(");
+      REGB0 = TAG_Int(8);
+      fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+      once_value_8 = fra.me.REG[4];
+      register_static_object(&once_value_8);
+    } else fra.me.REG[4] = once_value_8;
+    fra.me.REG[4] = fra.me.REG[4];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    /* compiling/compiling_icode.nit:1072 */
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
+    /* compiling/compiling_icode.nit:1073 */
+    if (!once_value_9) {
+      fra.me.REG[4] = BOX_NativeString(", ");
+      REGB0 = TAG_Int(2);
+      fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+      once_value_9 = fra.me.REG[4];
+      register_static_object(&once_value_9);
+    } else fra.me.REG[4] = once_value_9;
+    fra.me.REG[4] = fra.me.REG[4];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    /* compiling/compiling_icode.nit:1074 */
+    fra.me.REG[4] = CALL_compiling___compiling_base___MMGlobalProperty___vt_class_color(fra.me.REG[1])(fra.me.REG[1]);
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    /* compiling/compiling_icode.nit:1075 */
+    if (!once_value_10) {
+      fra.me.REG[4] = BOX_NativeString("(");
+      REGB0 = TAG_Int(1);
+      fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+      once_value_10 = fra.me.REG[4];
+      register_static_object(&once_value_10);
+    } else fra.me.REG[4] = once_value_10;
+    fra.me.REG[4] = fra.me.REG[4];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    /* compiling/compiling_icode.nit:1076 */
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1077 */
+    if (!once_value_11) {
+      fra.me.REG[4] = BOX_NativeString(")");
+      REGB0 = TAG_Int(1);
+      fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+      once_value_11 = fra.me.REG[4];
+      register_static_object(&once_value_11);
+    } else fra.me.REG[4] = once_value_11;
+    fra.me.REG[4] = fra.me.REG[4];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    /* compiling/compiling_icode.nit:1078 */
+    if (!once_value_12) {
+      fra.me.REG[4] = BOX_NativeString(", ");
+      REGB0 = TAG_Int(2);
+      fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB0);
+      once_value_12 = fra.me.REG[4];
+      register_static_object(&once_value_12);
+    } else fra.me.REG[4] = once_value_12;
+    fra.me.REG[4] = fra.me.REG[4];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    /* compiling/compiling_icode.nit:1079 */
+    fra.me.REG[1] = CALL_compiling___compiling_base___MMGlobalProperty___vt_class_id(fra.me.REG[1])(fra.me.REG[1]);
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
+    /* compiling/compiling_icode.nit:1080 */
+    if (!once_value_13) {
+      fra.me.REG[1] = BOX_NativeString("(");
+      REGB0 = TAG_Int(1);
+      fra.me.REG[1] = NEW_String_standard___string___String___with_native(fra.me.REG[1], REGB0);
+      once_value_13 = fra.me.REG[1];
+      register_static_object(&once_value_13);
+    } else fra.me.REG[1] = once_value_13;
+    fra.me.REG[1] = fra.me.REG[1];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
+    /* compiling/compiling_icode.nit:1081 */
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1082 */
+    if (!once_value_14) {
+      fra.me.REG[0] = BOX_NativeString(")");
+      REGB0 = TAG_Int(1);
+      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
+      once_value_14 = fra.me.REG[0];
+      register_static_object(&once_value_14);
+    } else fra.me.REG[0] = once_value_14;
+    fra.me.REG[0] = fra.me.REG[0];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1083 */
+    if (!once_value_15) {
+      fra.me.REG[0] = BOX_NativeString(")) /*cast ");
+      REGB0 = TAG_Int(10);
+      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
+      once_value_15 = fra.me.REG[0];
+      register_static_object(&once_value_15);
+    } else fra.me.REG[0] = once_value_15;
+    fra.me.REG[0] = fra.me.REG[0];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1084 */
+    fra.me.REG[0] = CALL_standard___string___Object___to_s(fra.me.REG[5])(fra.me.REG[5]);
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1085 */
+    if (!once_value_16) {
+      fra.me.REG[0] = BOX_NativeString("*/");
+      REGB0 = TAG_Int(2);
+      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
+      once_value_16 = fra.me.REG[0];
+      register_static_object(&once_value_16);
+    } else fra.me.REG[0] = once_value_16;
+    fra.me.REG[0] = fra.me.REG[0];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+  } else {
+    /* compiling/compiling_icode.nit:1087 */
+    fra.me.REG[0] = CALL_metamodel___static_type___MMType___local_class(fra.me.REG[5])(fra.me.REG[5]);
+    fra.me.REG[0] = CALL_metamodel___abstractmetamodel___MMLocalClass___global(fra.me.REG[0])(fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1088 */
+    if (!once_value_17) {
+      fra.me.REG[1] = BOX_NativeString("VAL_ISA(");
+      REGB0 = TAG_Int(8);
+      fra.me.REG[1] = NEW_String_standard___string___String___with_native(fra.me.REG[1], REGB0);
+      once_value_17 = fra.me.REG[1];
+      register_static_object(&once_value_17);
+    } else fra.me.REG[1] = once_value_17;
+    fra.me.REG[1] = fra.me.REG[1];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
+    /* compiling/compiling_icode.nit:1089 */
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
+    /* compiling/compiling_icode.nit:1090 */
+    if (!once_value_18) {
+      fra.me.REG[2] = BOX_NativeString(", ");
+      REGB0 = TAG_Int(2);
+      fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
+      once_value_18 = fra.me.REG[2];
+      register_static_object(&once_value_18);
+    } else fra.me.REG[2] = once_value_18;
+    fra.me.REG[2] = fra.me.REG[2];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
+    /* compiling/compiling_icode.nit:1091 */
+    fra.me.REG[2] = CALL_compiling___compiling_base___MMGlobalClass___color_id(fra.me.REG[0])(fra.me.REG[0]);
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
+    /* compiling/compiling_icode.nit:1092 */
+    if (!once_value_19) {
+      fra.me.REG[2] = BOX_NativeString(", ");
+      REGB0 = TAG_Int(2);
+      fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB0);
+      once_value_19 = fra.me.REG[2];
+      register_static_object(&once_value_19);
+    } else fra.me.REG[2] = once_value_19;
+    fra.me.REG[2] = fra.me.REG[2];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
+    /* compiling/compiling_icode.nit:1093 */
+    fra.me.REG[0] = CALL_compiling___compiling_base___MMGlobalClass___id_id(fra.me.REG[0])(fra.me.REG[0]);
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1094 */
+    if (!once_value_20) {
+      fra.me.REG[0] = BOX_NativeString(")) /*cast ");
+      REGB0 = TAG_Int(10);
+      fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
+      once_value_20 = fra.me.REG[0];
+      register_static_object(&once_value_20);
+    } else fra.me.REG[0] = once_value_20;
+    fra.me.REG[0] = fra.me.REG[0];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1095 */
+    fra.me.REG[5] = CALL_standard___string___Object___to_s(fra.me.REG[5])(fra.me.REG[5]);
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[5]);
+    /* compiling/compiling_icode.nit:1096 */
+    if (!once_value_21) {
+      fra.me.REG[5] = BOX_NativeString("*/");
+      REGB0 = TAG_Int(2);
+      fra.me.REG[5] = NEW_String_standard___string___String___with_native(fra.me.REG[5], REGB0);
+      once_value_21 = fra.me.REG[5];
+      register_static_object(&once_value_21);
+    } else fra.me.REG[5] = once_value_21;
+    fra.me.REG[5] = fra.me.REG[5];
+    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[5]);
+  }
    label1: while(0);
    stack_frame_head = fra.me.prev;
    return;
@@ -15042,10 +16652,11 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_15; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 1061;
+  fra.me.line = 1102;
    fra.me.meth = LOCATE_compiling___compiling_icode___IIs___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 6;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -15054,18 +16665,18 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
    fra.me.REG[5] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:1063 */
+  /* compiling/compiling_icode.nit:1104 */
    REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
      goto label1;
    }
-  /* ./compiling//compiling_icode.nit:1064 */
+  /* compiling/compiling_icode.nit:1105 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1065 */
+  /* compiling/compiling_icode.nit:1106 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1066 */
+  /* compiling/compiling_icode.nit:1107 */
    if (!once_value_2) {
      fra.me.REG[3] = BOX_NativeString("TAG_Bool(");
      REGB0 = TAG_Int(9);
@@ -15075,19 +16686,19 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[3] = once_value_2;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1067 */
+  /* compiling/compiling_icode.nit:1108 */
    fra.me.REG[3] = CALL_icode___icode_base___ICode2___expr1(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_icode___icode_base___IRegister___stype(fra.me.REG[3])(fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1068 */
+  /* compiling/compiling_icode.nit:1109 */
    fra.me.REG[4] = CALL_icode___icode_base___ICode2___expr2(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[4] = CALL_icode___icode_base___IRegister___stype(fra.me.REG[4])(fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:1069 */
+  /* compiling/compiling_icode.nit:1110 */
    REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[3], COLOR_metamodel___static_type___MMTypeNone, ID_metamodel___static_type___MMTypeNone)) /*cast MMTypeNone*/;
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:1070 */
+    /* compiling/compiling_icode.nit:1111 */
      REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[4], COLOR_metamodel___static_type___MMTypeNone, ID_metamodel___static_type___MMTypeNone)) /*cast MMTypeNone*/;
      if (UNTAG_Bool(REGB0)) {
-      /* ./compiling//compiling_icode.nit:1071 */
+      /* compiling/compiling_icode.nit:1112 */
        if (!once_value_3) {
          fra.me.REG[5] = BOX_NativeString("1)");
          REGB0 = TAG_Int(2);
@@ -15097,17 +16708,17 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
        } else fra.me.REG[5] = once_value_3;
        fra.me.REG[5] = fra.me.REG[5];
        CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[5]);
-      /* ./compiling//compiling_icode.nit:1072 */
+      /* compiling/compiling_icode.nit:1113 */
        goto label1;
      } else {
-      /* ./compiling//compiling_icode.nit:1073 */
+      /* compiling/compiling_icode.nit:1114 */
        REGB0 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[4])(fra.me.REG[4]);
        if (UNTAG_Bool(REGB0)) {
-        /* ./compiling//compiling_icode.nit:1074 */
+        /* compiling/compiling_icode.nit:1115 */
          fra.me.REG[5] = CALL_icode___icode_base___ICode2___expr2(fra.me.REG[0])(fra.me.REG[0]);
          fra.me.REG[5] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
          CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[5]);
-        /* ./compiling//compiling_icode.nit:1075 */
+        /* compiling/compiling_icode.nit:1116 */
          if (!once_value_4) {
            fra.me.REG[5] = BOX_NativeString("==NIT_NULL)");
            REGB0 = TAG_Int(11);
@@ -15117,10 +16728,10 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
          } else fra.me.REG[5] = once_value_4;
          fra.me.REG[5] = fra.me.REG[5];
          CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[5]);
-        /* ./compiling//compiling_icode.nit:1076 */
+        /* compiling/compiling_icode.nit:1117 */
          goto label1;
        } else {
-        /* ./compiling//compiling_icode.nit:1078 */
+        /* compiling/compiling_icode.nit:1119 */
          if (!once_value_5) {
            fra.me.REG[5] = BOX_NativeString("0)");
            REGB0 = TAG_Int(2);
@@ -15130,22 +16741,22 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
          } else fra.me.REG[5] = once_value_5;
          fra.me.REG[5] = fra.me.REG[5];
          CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[5]);
-        /* ./compiling//compiling_icode.nit:1079 */
+        /* compiling/compiling_icode.nit:1120 */
          goto label1;
        }
      }
    } else {
-    /* ./compiling//compiling_icode.nit:1081 */
+    /* compiling/compiling_icode.nit:1122 */
      REGB0 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[3])(fra.me.REG[3]);
      if (UNTAG_Bool(REGB0)) {
-      /* ./compiling//compiling_icode.nit:1082 */
+      /* compiling/compiling_icode.nit:1123 */
        REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[4], COLOR_metamodel___static_type___MMTypeNone, ID_metamodel___static_type___MMTypeNone)) /*cast MMTypeNone*/;
        if (UNTAG_Bool(REGB0)) {
-        /* ./compiling//compiling_icode.nit:1083 */
+        /* compiling/compiling_icode.nit:1124 */
          fra.me.REG[3] = CALL_icode___icode_base___ICode2___expr1(fra.me.REG[0])(fra.me.REG[0]);
          fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
          CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-        /* ./compiling//compiling_icode.nit:1084 */
+        /* compiling/compiling_icode.nit:1125 */
          if (!once_value_6) {
            fra.me.REG[3] = BOX_NativeString("==NIT_NULL)");
            REGB0 = TAG_Int(11);
@@ -15155,13 +16766,13 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
          } else fra.me.REG[3] = once_value_6;
          fra.me.REG[3] = fra.me.REG[3];
          CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-        /* ./compiling//compiling_icode.nit:1085 */
+        /* compiling/compiling_icode.nit:1126 */
          goto label1;
        } else {
-        /* ./compiling//compiling_icode.nit:1086 */
+        /* compiling/compiling_icode.nit:1127 */
          REGB0 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[4])(fra.me.REG[4]);
          if (UNTAG_Bool(REGB0)) {
-          /* ./compiling//compiling_icode.nit:1087 */
+          /* compiling/compiling_icode.nit:1128 */
            if (!once_value_7) {
              fra.me.REG[3] = BOX_NativeString("IS_EQUAL_NN(");
              REGB0 = TAG_Int(12);
@@ -15172,7 +16783,7 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
            fra.me.REG[3] = fra.me.REG[3];
            CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
          } else {
-          /* ./compiling//compiling_icode.nit:1089 */
+          /* compiling/compiling_icode.nit:1130 */
            if (!once_value_8) {
              fra.me.REG[3] = BOX_NativeString("IS_EQUAL_ON(");
              REGB0 = TAG_Int(12);
@@ -15182,11 +16793,11 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
            } else fra.me.REG[3] = once_value_8;
            fra.me.REG[3] = fra.me.REG[3];
            CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-          /* ./compiling//compiling_icode.nit:1090 */
+          /* compiling/compiling_icode.nit:1131 */
            fra.me.REG[3] = CALL_icode___icode_base___ICode2___expr2(fra.me.REG[0])(fra.me.REG[0]);
            fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
            CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-          /* ./compiling//compiling_icode.nit:1091 */
+          /* compiling/compiling_icode.nit:1132 */
            if (!once_value_9) {
              fra.me.REG[3] = BOX_NativeString(",");
              REGB0 = TAG_Int(1);
@@ -15196,11 +16807,11 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
            } else fra.me.REG[3] = once_value_9;
            fra.me.REG[3] = fra.me.REG[3];
            CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-          /* ./compiling//compiling_icode.nit:1092 */
+          /* compiling/compiling_icode.nit:1133 */
            fra.me.REG[3] = CALL_icode___icode_base___ICode2___expr1(fra.me.REG[0])(fra.me.REG[0]);
            fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
            CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-          /* ./compiling//compiling_icode.nit:1093 */
+          /* compiling/compiling_icode.nit:1134 */
            if (!once_value_10) {
              fra.me.REG[3] = BOX_NativeString("))");
              REGB0 = TAG_Int(2);
@@ -15210,15 +16821,15 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
            } else fra.me.REG[3] = once_value_10;
            fra.me.REG[3] = fra.me.REG[3];
            CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-          /* ./compiling//compiling_icode.nit:1094 */
+          /* compiling/compiling_icode.nit:1135 */
            goto label1;
          }
        }
      } else {
-      /* ./compiling//compiling_icode.nit:1097 */
+      /* compiling/compiling_icode.nit:1138 */
        REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[4], COLOR_metamodel___static_type___MMTypeNone, ID_metamodel___static_type___MMTypeNone)) /*cast MMTypeNone*/;
        if (UNTAG_Bool(REGB0)) {
-        /* ./compiling//compiling_icode.nit:1098 */
+        /* compiling/compiling_icode.nit:1139 */
          if (!once_value_11) {
            fra.me.REG[3] = BOX_NativeString("0)");
            REGB0 = TAG_Int(2);
@@ -15228,13 +16839,13 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
          } else fra.me.REG[3] = once_value_11;
          fra.me.REG[3] = fra.me.REG[3];
          CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-        /* ./compiling//compiling_icode.nit:1099 */
+        /* compiling/compiling_icode.nit:1140 */
          goto label1;
        } else {
-        /* ./compiling//compiling_icode.nit:1100 */
+        /* compiling/compiling_icode.nit:1141 */
          REGB0 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[4])(fra.me.REG[4]);
          if (UNTAG_Bool(REGB0)) {
-          /* ./compiling//compiling_icode.nit:1101 */
+          /* compiling/compiling_icode.nit:1142 */
            if (!once_value_12) {
              fra.me.REG[4] = BOX_NativeString("IS_EQUAL_ON(");
              REGB0 = TAG_Int(12);
@@ -15245,7 +16856,7 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
            fra.me.REG[4] = fra.me.REG[4];
            CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
          } else {
-          /* ./compiling//compiling_icode.nit:1103 */
+          /* compiling/compiling_icode.nit:1144 */
            if (!once_value_13) {
              fra.me.REG[4] = BOX_NativeString("IS_EQUAL_OO(");
              REGB0 = TAG_Int(12);
@@ -15259,11 +16870,11 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
        }
      }
    }
-  /* ./compiling//compiling_icode.nit:1106 */
+  /* compiling/compiling_icode.nit:1147 */
    fra.me.REG[4] = CALL_icode___icode_base___ICode2___expr1(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[4] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:1107 */
+  /* compiling/compiling_icode.nit:1148 */
    if (!once_value_14) {
      fra.me.REG[4] = BOX_NativeString(",");
      REGB0 = TAG_Int(1);
@@ -15273,11 +16884,11 @@ void compiling___compiling_icode___IIs___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[4] = once_value_14;
    fra.me.REG[4] = fra.me.REG[4];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:1108 */
+  /* compiling/compiling_icode.nit:1149 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode2___expr2(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:1109 */
+  /* compiling/compiling_icode.nit:1150 */
    if (!once_value_15) {
      fra.me.REG[0] = BOX_NativeString("))");
      REGB0 = TAG_Int(2);
@@ -15299,28 +16910,29 @@ void compiling___compiling_icode___INot___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_3; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 1114;
+  fra.me.line = 1155;
    fra.me.meth = LOCATE_compiling___compiling_icode___INot___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 4;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
    fra.me.REG[3] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:1116 */
+  /* compiling/compiling_icode.nit:1157 */
    REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
      goto label1;
    }
-  /* ./compiling//compiling_icode.nit:1117 */
+  /* compiling/compiling_icode.nit:1158 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1118 */
+  /* compiling/compiling_icode.nit:1159 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1119 */
+  /* compiling/compiling_icode.nit:1160 */
    if (!once_value_2) {
      fra.me.REG[3] = BOX_NativeString("TAG_Bool(!UNTAG_Bool(");
      REGB0 = TAG_Int(21);
@@ -15330,11 +16942,11 @@ void compiling___compiling_icode___INot___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[3] = once_value_2;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1120 */
+  /* compiling/compiling_icode.nit:1161 */
    fra.me.REG[0] = CALL_icode___icode_base___ICode1___expr(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:1121 */
+  /* compiling/compiling_icode.nit:1162 */
    if (!once_value_3) {
      fra.me.REG[0] = BOX_NativeString("))");
      REGB0 = TAG_Int(2);
@@ -15374,10 +16986,11 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_19; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 1126;
+  fra.me.line = 1167;
    fra.me.meth = LOCATE_compiling___compiling_icode___IOnce___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 6;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -15386,25 +16999,27 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
    fra.me.REG[5] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:1128 */
-  fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
-  CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1129 */
+  /* compiling/compiling_icode.nit:1167 */
+  fra.me.REG[2] = fra.me.REG[0];
+  /* compiling/compiling_icode.nit:1169 */
+  fra.me.REG[3] = CALL_icode___icode_base___ICode___location(fra.me.REG[2])(fra.me.REG[2]);
+  CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:1170 */
    REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___new_number(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1130 */
-  fra.me.REG[2] = CALL_icode___icode_base___ICode___result(fra.me.REG[0])(fra.me.REG[0]);
-  REGB1 = TAG_Bool((fra.me.REG[2]!=NIT_NULL) && VAL_ISA(fra.me.REG[2], COLOR_icode___icode_base___IRegister, ID_icode___icode_base___IRegister)) /*cast IRegister*/;
+  /* compiling/compiling_icode.nit:1171 */
+  fra.me.REG[3] = CALL_icode___icode_base___ICode___result(fra.me.REG[2])(fra.me.REG[2]);
+  REGB1 = TAG_Bool((fra.me.REG[3]!=NIT_NULL) && VAL_ISA(fra.me.REG[3], COLOR_icode___icode_base___IRegister, ID_icode___icode_base___IRegister)) /*cast IRegister*/;
    if (UNTAG_Bool(REGB1)) {
    } else {
-    nit_abort("Cast failed", NULL, LOCATE_compiling___compiling_icode, 1130);
+    nit_abort("Cast failed", NULL, LOCATE_compiling___compiling_icode, 1171);
    }
-  /* ./compiling//compiling_icode.nit:1131 */
-  fra.me.REG[3] = CALL_icode___icode_base___IRegister___stype(fra.me.REG[2])(fra.me.REG[2]);
-  REGB1 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[3])(fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:1172 */
+  fra.me.REG[0] = CALL_icode___icode_base___IRegister___stype(fra.me.REG[3])(fra.me.REG[3]);
+  REGB1 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[0])(fra.me.REG[0]);
    if (UNTAG_Bool(REGB1)) {
-    /* ./compiling//compiling_icode.nit:1132 */
+    /* compiling/compiling_icode.nit:1173 */
      REGB1 = TAG_Int(5);
-    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
+    fra.me.REG[0] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
      if (!once_value_1) {
        fra.me.REG[4] = BOX_NativeString("static val_t once_value_");
        REGB1 = TAG_Int(24);
@@ -15413,9 +17028,9 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_1);
      } else fra.me.REG[4] = once_value_1;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      if (!once_value_2) {
        fra.me.REG[4] = BOX_NativeString("; static int once_bool_");
        REGB1 = TAG_Int(23);
@@ -15424,9 +17039,9 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_2);
      } else fra.me.REG[4] = once_value_2;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      if (!once_value_3) {
        fra.me.REG[4] = BOX_NativeString("; /* Once value */");
        REGB1 = TAG_Int(18);
@@ -15435,12 +17050,12 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_3);
      } else fra.me.REG[4] = once_value_3;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
-    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:1133 */
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
+    fra.me.REG[0] = CALL_standard___string___Object___to_s(fra.me.REG[0])(fra.me.REG[0]);
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1174 */
      REGB1 = TAG_Int(3);
-    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
+    fra.me.REG[0] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
      if (!once_value_4) {
        fra.me.REG[4] = BOX_NativeString("if (!once_bool_");
        REGB1 = TAG_Int(15);
@@ -15449,9 +17064,9 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_4);
      } else fra.me.REG[4] = once_value_4;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      if (!once_value_5) {
        fra.me.REG[4] = BOX_NativeString(") {");
        REGB1 = TAG_Int(3);
@@ -15460,13 +17075,13 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_5);
      } else fra.me.REG[4] = once_value_5;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
-    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
+    fra.me.REG[0] = CALL_standard___string___Object___to_s(fra.me.REG[0])(fra.me.REG[0]);
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    } else {
-    /* ./compiling//compiling_icode.nit:1136 */
+    /* compiling/compiling_icode.nit:1177 */
      REGB1 = TAG_Int(3);
-    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
+    fra.me.REG[0] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
      if (!once_value_6) {
        fra.me.REG[4] = BOX_NativeString("static val_t once_value_");
        REGB1 = TAG_Int(24);
@@ -15475,9 +17090,9 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_6);
      } else fra.me.REG[4] = once_value_6;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      if (!once_value_7) {
        fra.me.REG[4] = BOX_NativeString("; /* Once value */");
        REGB1 = TAG_Int(18);
@@ -15486,12 +17101,12 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_7);
      } else fra.me.REG[4] = once_value_7;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
-    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:1137 */
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
+    fra.me.REG[0] = CALL_standard___string___Object___to_s(fra.me.REG[0])(fra.me.REG[0]);
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_decl(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
+    /* compiling/compiling_icode.nit:1178 */
      REGB1 = TAG_Int(3);
-    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
+    fra.me.REG[0] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
      if (!once_value_8) {
        fra.me.REG[4] = BOX_NativeString("if (!once_value_");
        REGB1 = TAG_Int(16);
@@ -15500,9 +17115,9 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_8);
      } else fra.me.REG[4] = once_value_8;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
      if (!once_value_9) {
        fra.me.REG[4] = BOX_NativeString(") {");
        REGB1 = TAG_Int(3);
@@ -15511,18 +17126,18 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_9);
      } else fra.me.REG[4] = once_value_9;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
-    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
+    fra.me.REG[0] = CALL_standard___string___Object___to_s(fra.me.REG[0])(fra.me.REG[0]);
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    }
-  /* ./compiling//compiling_icode.nit:1139 */
+  /* compiling/compiling_icode.nit:1180 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___indent(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1140 */
-  fra.me.REG[3] = CALL_icode___icode_base___IOnce___body(fra.me.REG[0])(fra.me.REG[0]);
-  CALL_compiling___compiling_icode___ICode___compile_to_c(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1141 */
-  fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1142 */
+  /* compiling/compiling_icode.nit:1181 */
+  fra.me.REG[0] = CALL_icode___icode_base___IOnce___body(fra.me.REG[2])(fra.me.REG[2]);
+  CALL_compiling___compiling_icode___ICode___compile_to_c(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
+  /* compiling/compiling_icode.nit:1182 */
+  fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___register(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:1183 */
    REGB1 = TAG_Int(5);
    fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
    if (!once_value_10) {
@@ -15545,7 +17160,7 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[5] = once_value_11;
    fra.me.REG[5] = fra.me.REG[5];
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
-  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
+  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[0]);
    if (!once_value_12) {
      fra.me.REG[5] = BOX_NativeString(";");
      REGB1 = TAG_Int(1);
@@ -15557,7 +17172,7 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
    fra.me.REG[4] = CALL_standard___string___Object___to_s(fra.me.REG[4])(fra.me.REG[4]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:1143 */
+  /* compiling/compiling_icode.nit:1184 */
    REGB1 = TAG_Int(3);
    fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
    if (!once_value_13) {
@@ -15582,12 +17197,12 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
    fra.me.REG[4] = CALL_standard___string___Object___to_s(fra.me.REG[4])(fra.me.REG[4]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:1144 */
-  fra.me.REG[2] = CALL_icode___icode_base___IRegister___stype(fra.me.REG[2])(fra.me.REG[2]);
-  REGB1 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[2])(fra.me.REG[2]);
+  /* compiling/compiling_icode.nit:1185 */
+  fra.me.REG[3] = CALL_icode___icode_base___IRegister___stype(fra.me.REG[3])(fra.me.REG[3]);
+  REGB1 = CALL_metamodel___static_type___MMType___is_nullable(fra.me.REG[3])(fra.me.REG[3]);
    if (UNTAG_Bool(REGB1)) {
      REGB1 = TAG_Int(3);
-    fra.me.REG[2] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
+    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
      if (!once_value_15) {
        fra.me.REG[4] = BOX_NativeString("once_bool_");
        REGB1 = TAG_Int(10);
@@ -15596,9 +17211,9 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_15);
      } else fra.me.REG[4] = once_value_15;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
      fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
      if (!once_value_16) {
        fra.me.REG[4] = BOX_NativeString(" = true;");
        REGB1 = TAG_Int(8);
@@ -15607,15 +17222,15 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
        register_static_object(&once_value_16);
      } else fra.me.REG[4] = once_value_16;
      fra.me.REG[4] = fra.me.REG[4];
-    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
-    fra.me.REG[2] = CALL_standard___string___Object___to_s(fra.me.REG[2])(fra.me.REG[2]);
-    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
+    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
    }
-  /* ./compiling//compiling_icode.nit:1145 */
+  /* compiling/compiling_icode.nit:1186 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___unindent(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1146 */
+  /* compiling/compiling_icode.nit:1187 */
    REGB1 = TAG_Int(5);
-  fra.me.REG[2] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
+  fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
    if (!once_value_17) {
      fra.me.REG[4] = BOX_NativeString("} else ");
      REGB1 = TAG_Int(7);
@@ -15624,8 +17239,8 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
      register_static_object(&once_value_17);
    } else fra.me.REG[4] = once_value_17;
    fra.me.REG[4] = fra.me.REG[4];
-  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
-  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
+  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[0]);
    if (!once_value_18) {
      fra.me.REG[4] = BOX_NativeString(" = once_value_");
      REGB1 = TAG_Int(14);
@@ -15634,9 +17249,9 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
      register_static_object(&once_value_18);
    } else fra.me.REG[4] = once_value_18;
    fra.me.REG[4] = fra.me.REG[4];
-  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
+  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
    fra.me.REG[4] = CALL_standard___string___Object___to_s(REGB0)(REGB0);
-  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
+  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
    if (!once_value_19) {
      fra.me.REG[4] = BOX_NativeString(";");
      REGB0 = TAG_Int(1);
@@ -15645,13 +17260,13 @@ void compiling___compiling_icode___IOnce___compile_to_c(val_t p0, val_t p1){
      register_static_object(&once_value_19);
    } else fra.me.REG[4] = once_value_19;
    fra.me.REG[4] = fra.me.REG[4];
-  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
-  fra.me.REG[2] = CALL_standard___string___Object___to_s(fra.me.REG[2])(fra.me.REG[2]);
-  CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1147 */
-  fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1148 */
-  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+  CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
+  fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
+  CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+  /* compiling/compiling_icode.nit:1188 */
+  fra.me.REG[1] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+  /* compiling/compiling_icode.nit:1189 */
+  CALL_compiling___compiling_writer___Writer___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    stack_frame_head = fra.me.prev;
    return;
  }
@@ -15676,10 +17291,11 @@ void compiling___compiling_icode___IClosCall___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_14; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 1153;
+  fra.me.line = 1194;
    fra.me.meth = LOCATE_compiling___compiling_icode___IClosCall___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 7;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -15689,13 +17305,13 @@ void compiling___compiling_icode___IClosCall___compile_to_c(val_t p0, val_t p1){
    fra.me.REG[6] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:1155 */
+  /* compiling/compiling_icode.nit:1196 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1158 */
+  /* compiling/compiling_icode.nit:1199 */
    REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___closure(fra.me.REG[1])(fra.me.REG[1]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:1159 */
+    /* compiling/compiling_icode.nit:1200 */
      REGB0 = TAG_Int(3);
      fra.me.REG[2] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
      if (!once_value_1) {
@@ -15721,7 +17337,7 @@ void compiling___compiling_icode___IClosCall___compile_to_c(val_t p0, val_t p1){
      fra.me.REG[4] = fra.me.REG[4];
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
      fra.me.REG[2] = CALL_standard___string___Object___to_s(fra.me.REG[2])(fra.me.REG[2]);
-    /* ./compiling//compiling_icode.nit:1160 */
+    /* compiling/compiling_icode.nit:1201 */
      REGB0 = TAG_Int(1);
      fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
      if (!once_value_3) {
@@ -15734,7 +17350,7 @@ void compiling___compiling_icode___IClosCall___compile_to_c(val_t p0, val_t p1){
      fra.me.REG[3] = fra.me.REG[3];
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
    } else {
-    /* ./compiling//compiling_icode.nit:1162 */
+    /* compiling/compiling_icode.nit:1203 */
      REGB0 = TAG_Int(3);
      fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
      if (!once_value_4) {
@@ -15761,7 +17377,7 @@ void compiling___compiling_icode___IClosCall___compile_to_c(val_t p0, val_t p1){
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[6]);
      fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
      fra.me.REG[2] = fra.me.REG[3];
-    /* ./compiling//compiling_icode.nit:1163 */
+    /* compiling/compiling_icode.nit:1204 */
      REGB0 = TAG_Int(1);
      fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
      if (!once_value_6) {
@@ -15775,11 +17391,11 @@ void compiling___compiling_icode___IClosCall___compile_to_c(val_t p0, val_t p1){
      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[6]);
      fra.me.REG[4] = fra.me.REG[3];
    }
-  /* ./compiling//compiling_icode.nit:1165 */
+  /* compiling/compiling_icode.nit:1206 */
    fra.me.REG[3] = CALL_icode___icode_base___ICodeN___exprs(fra.me.REG[0])(fra.me.REG[0]);
    fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___registers(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
    CALL_standard___collection___abstract_collection___Sequence___append(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1167 */
+  /* compiling/compiling_icode.nit:1208 */
    REGB0 = TAG_Int(7);
    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    if (!once_value_7) {
@@ -15834,13 +17450,13 @@ void compiling___compiling_icode___IClosCall___compile_to_c(val_t p0, val_t p1){
    fra.me.REG[2] = fra.me.REG[2];
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[2]);
    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1168 */
+  /* compiling/compiling_icode.nit:1209 */
    fra.me.REG[2] = NEW_Writer_compiling___compiling_writer___Writer___init();
-  /* ./compiling//compiling_icode.nit:1169 */
+  /* compiling/compiling_icode.nit:1210 */
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1170 */
+  /* compiling/compiling_icode.nit:1211 */
    CALL_compiling___compiling_icode___ICode___store_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1173 */
+  /* compiling/compiling_icode.nit:1214 */
    REGB0 = TAG_Int(3);
    fra.me.REG[2] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    if (!once_value_12) {
@@ -15865,11 +17481,11 @@ void compiling___compiling_icode___IClosCall___compile_to_c(val_t p0, val_t p1){
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
    fra.me.REG[2] = CALL_standard___string___Object___to_s(fra.me.REG[2])(fra.me.REG[2]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1174 */
+  /* compiling/compiling_icode.nit:1215 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___indent(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1175 */
+  /* compiling/compiling_icode.nit:1216 */
    fra.me.REG[0] = CALL_icode___icode_base___IClosCall___break_seq(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:1176 */
+  /* compiling/compiling_icode.nit:1217 */
    REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
    if (UNTAG_Bool(REGB0)) {
    } else {
@@ -15884,20 +17500,20 @@ void compiling___compiling_icode___IClosCall___compile_to_c(val_t p0, val_t p1){
    }
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:1177 */
+    /* compiling/compiling_icode.nit:1218 */
      REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
      if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 1177);
+      nit_abort("Reciever is null", NULL, LOCATE_compiling___compiling_icode, 1218);
      }
      CALL_compiling___compiling_icode___ICode___compile_to_c(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
    }
-  /* ./compiling//compiling_icode.nit:1179 */
+  /* compiling/compiling_icode.nit:1220 */
    fra.me.REG[0] = CALL_compiling___compiling_icode___I2CCompilerVisitor___iroutine(fra.me.REG[1])(fra.me.REG[1]);
    fra.me.REG[0] = CALL_icode___icode_base___IRoutine___body(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_goto(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:1180 */
+  /* compiling/compiling_icode.nit:1221 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___unindent(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1181 */
+  /* compiling/compiling_icode.nit:1222 */
    if (!once_value_14) {
      fra.me.REG[0] = BOX_NativeString("}");
      REGB0 = TAG_Int(1);
@@ -15922,10 +17538,11 @@ void compiling___compiling_icode___IHasClos___compile_to_c(val_t p0, val_t p1){
    static val_t once_value_7; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 1186;
+  fra.me.line = 1227;
    fra.me.meth = LOCATE_compiling___compiling_icode___IHasClos___compile_to_c;
    fra.me.has_broke = 0;
    fra.me.REG_size = 5;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -15933,18 +17550,18 @@ void compiling___compiling_icode___IHasClos___compile_to_c(val_t p0, val_t p1){
    fra.me.REG[4] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:1188 */
+  /* compiling/compiling_icode.nit:1229 */
    REGB0 = CALL_compiling___compiling_icode___ICode___need_result(fra.me.REG[0])(fra.me.REG[0]);
    REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
    if (UNTAG_Bool(REGB0)) {
      goto label1;
    }
-  /* ./compiling//compiling_icode.nit:1189 */
+  /* compiling/compiling_icode.nit:1230 */
    fra.me.REG[2] = CALL_icode___icode_base___ICode___location(fra.me.REG[0])(fra.me.REG[0]);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_location(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1190 */
+  /* compiling/compiling_icode.nit:1231 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___ICode___new_result(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1191 */
+  /* compiling/compiling_icode.nit:1232 */
    if (!once_value_2) {
      fra.me.REG[3] = BOX_NativeString("TAG_Bool(");
      REGB0 = TAG_Int(9);
@@ -15954,10 +17571,10 @@ void compiling___compiling_icode___IHasClos___compile_to_c(val_t p0, val_t p1){
    } else fra.me.REG[3] = once_value_2;
    fra.me.REG[3] = fra.me.REG[3];
    CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1192 */
+  /* compiling/compiling_icode.nit:1233 */
    REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___closure(fra.me.REG[1])(fra.me.REG[1]);
    if (UNTAG_Bool(REGB0)) {
-    /* ./compiling//compiling_icode.nit:1193 */
+    /* compiling/compiling_icode.nit:1234 */
      if (!once_value_3) {
        fra.me.REG[3] = BOX_NativeString("closctx->closure_funs[");
        REGB0 = TAG_Int(22);
@@ -15967,12 +17584,12 @@ void compiling___compiling_icode___IHasClos___compile_to_c(val_t p0, val_t p1){
      } else fra.me.REG[3] = once_value_3;
      fra.me.REG[3] = fra.me.REG[3];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
-    /* ./compiling//compiling_icode.nit:1194 */
+    /* compiling/compiling_icode.nit:1235 */
      fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___closures(fra.me.REG[1])(fra.me.REG[1]);
      fra.me.REG[4] = CALL_icode___icode_base___IHasClos___closure_decl(fra.me.REG[0])(fra.me.REG[0]);
      fra.me.REG[4] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[4]);
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
-    /* ./compiling//compiling_icode.nit:1195 */
+    /* compiling/compiling_icode.nit:1236 */
      if (!once_value_4) {
        fra.me.REG[4] = BOX_NativeString("]");
        REGB0 = TAG_Int(1);
@@ -15983,7 +17600,7 @@ void compiling___compiling_icode___IHasClos___compile_to_c(val_t p0, val_t p1){
      fra.me.REG[4] = fra.me.REG[4];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
    } else {
-    /* ./compiling//compiling_icode.nit:1197 */
+    /* compiling/compiling_icode.nit:1238 */
      if (!once_value_5) {
        fra.me.REG[4] = BOX_NativeString("CREG[");
        REGB0 = TAG_Int(5);
@@ -15993,12 +17610,12 @@ void compiling___compiling_icode___IHasClos___compile_to_c(val_t p0, val_t p1){
      } else fra.me.REG[4] = once_value_5;
      fra.me.REG[4] = fra.me.REG[4];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
-    /* ./compiling//compiling_icode.nit:1198 */
+    /* compiling/compiling_icode.nit:1239 */
      fra.me.REG[1] = CALL_compiling___compiling_icode___I2CCompilerVisitor___closures(fra.me.REG[1])(fra.me.REG[1]);
      fra.me.REG[0] = CALL_icode___icode_base___IHasClos___closure_decl(fra.me.REG[0])(fra.me.REG[0]);
      fra.me.REG[0] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
-    /* ./compiling//compiling_icode.nit:1199 */
+    /* compiling/compiling_icode.nit:1240 */
      if (!once_value_6) {
        fra.me.REG[0] = BOX_NativeString("]");
        REGB0 = TAG_Int(1);
@@ -16009,7 +17626,7 @@ void compiling___compiling_icode___IHasClos___compile_to_c(val_t p0, val_t p1){
      fra.me.REG[0] = fra.me.REG[0];
      CALL_compiling___compiling_writer___Writer___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[0]);
    }
-  /* ./compiling//compiling_icode.nit:1201 */
+  /* compiling/compiling_icode.nit:1242 */
    if (!once_value_7) {
      fra.me.REG[0] = BOX_NativeString(" != NULL)");
      REGB0 = TAG_Int(9);
@@ -16041,10 +17658,11 @@ val_t compiling___compiling_icode___IClosureDef___compile_closure(val_t p0, val_
    static val_t once_value_10; /* Once value */
    fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
    fra.me.file = LOCATE_compiling___compiling_icode;
-  fra.me.line = 1206;
+  fra.me.line = 1247;
    fra.me.meth = LOCATE_compiling___compiling_icode___IClosureDef___compile_closure;
    fra.me.has_broke = 0;
    fra.me.REG_size = 9;
+  fra.me.nitni_local_ref_head = NULL;
    fra.me.REG[0] = NIT_NULL;
    fra.me.REG[1] = NIT_NULL;
    fra.me.REG[2] = NIT_NULL;
@@ -16056,31 +17674,31 @@ val_t compiling___compiling_icode___IClosureDef___compile_closure(val_t p0, val_
    fra.me.REG[8] = NIT_NULL;
    fra.me.REG[0] = p0;
    fra.me.REG[1] = p1;
-  /* ./compiling//compiling_icode.nit:1210 */
+  /* compiling/compiling_icode.nit:1251 */
    fra.me.REG[2] = CALL_compiling___compiling_icode___I2CCompilerVisitor___visitor(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1213 */
+  /* compiling/compiling_icode.nit:1254 */
    REGB0 = CALL_compiling___compiling_icode___I2CCompilerVisitor___closure(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1214 */
+  /* compiling/compiling_icode.nit:1255 */
    REGB1 = TAG_Bool(true);
    CALL_compiling___compiling_icode___I2CCompilerVisitor___closure__eq(fra.me.REG[1])(fra.me.REG[1], REGB1);
-  /* ./compiling//compiling_icode.nit:1217 */
+  /* compiling/compiling_icode.nit:1258 */
    fra.me.REG[3] = CALL_compiling___compiling_icode___I2CCompilerVisitor___local_labels(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1218 */
+  /* compiling/compiling_icode.nit:1259 */
    fra.me.REG[4] = NEW_HashSet_standard___collection___hash_collection___HashSet___init();
    CALL_compiling___compiling_icode___I2CCompilerVisitor___local_labels__eq(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:1221 */
+  /* compiling/compiling_icode.nit:1262 */
    fra.me.REG[4] = CALL_compiling___compiling_base___CompilerVisitor___decl_writer(fra.me.REG[2])(fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1222 */
+  /* compiling/compiling_icode.nit:1263 */
    fra.me.REG[5] = CALL_compiling___compiling_base___CompilerVisitor___writer(fra.me.REG[2])(fra.me.REG[2]);
-  /* ./compiling//compiling_icode.nit:1223 */
+  /* compiling/compiling_icode.nit:1264 */
    fra.me.REG[6] = CALL_compiling___compiling_base___CompilerVisitor___top_writer(fra.me.REG[2])(fra.me.REG[2]);
    fra.me.REG[6] = CALL_compiling___compiling_writer___Writer___sub(fra.me.REG[6])(fra.me.REG[6]);
    CALL_compiling___compiling_base___CompilerVisitor___writer__eq(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[6]);
-  /* ./compiling//compiling_icode.nit:1224 */
+  /* compiling/compiling_icode.nit:1265 */
    fra.me.REG[6] = CALL_compiling___compiling_base___CompilerVisitor___header_writer(fra.me.REG[2])(fra.me.REG[2]);
    fra.me.REG[6] = CALL_compiling___compiling_writer___Writer___sub(fra.me.REG[6])(fra.me.REG[6]);
    CALL_compiling___compiling_base___CompilerVisitor___decl_writer__eq(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[6]);
-  /* ./compiling//compiling_icode.nit:1227 */
+  /* compiling/compiling_icode.nit:1268 */
    REGB1 = TAG_Int(5);
    fra.me.REG[6] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
    if (!once_value_1) {
@@ -16116,7 +17734,7 @@ val_t compiling___compiling_icode___IClosureDef___compile_closure(val_t p0, val_
    fra.me.REG[7] = fra.me.REG[7];
    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[6])(fra.me.REG[6], fra.me.REG[7]);
    fra.me.REG[6] = CALL_standard___string___Object___to_s(fra.me.REG[6])(fra.me.REG[6]);
-  /* ./compiling//compiling_icode.nit:1228 */
+  /* compiling/compiling_icode.nit:1269 */
    fra.me.REG[7] = CALL_compiling___compiling_icode___I2CCompilerVisitor___visitor(fra.me.REG[1])(fra.me.REG[1]);
    if (!once_value_4) {
      fra.me.REG[8] = BOX_NativeString("struct stack_frame_t *closctx");
@@ -16127,13 +17745,13 @@ val_t compiling___compiling_icode___IClosureDef___compile_closure(val_t p0, val_
    } else fra.me.REG[8] = once_value_4;
    fra.me.REG[8] = fra.me.REG[8];
    fra.me.REG[8] = CALL_compiling___compiling_icode___IRoutine___compile_signature_to_c(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[7], fra.me.REG[6], NIT_NULL, fra.me.REG[8], NIT_NULL);
-  /* ./compiling//compiling_icode.nit:1229 */
+  /* compiling/compiling_icode.nit:1270 */
    fra.me.REG[7] = CALL_compiling___compiling_base___CompilerVisitor___writer(fra.me.REG[2])(fra.me.REG[2]);
    fra.me.REG[7] = CALL_compiling___compiling_writer___Writer___sub(fra.me.REG[7])(fra.me.REG[7]);
    CALL_compiling___compiling_base___CompilerVisitor___decl_writer__eq(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[7]);
-  /* ./compiling//compiling_icode.nit:1231 */
+  /* compiling/compiling_icode.nit:1272 */
    fra.me.REG[8] = CALL_compiling___compiling_icode___IRoutine___compile_inside_to_c(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1], fra.me.REG[8]);
-  /* ./compiling//compiling_icode.nit:1232 */
+  /* compiling/compiling_icode.nit:1273 */
    REGB1 = TAG_Bool(fra.me.REG[8]==NIT_NULL);
    if (UNTAG_Bool(REGB1)) {
    } else {
@@ -16147,7 +17765,7 @@ val_t compiling___compiling_icode___IClosureDef___compile_closure(val_t p0, val_
      }
    }
    if (UNTAG_Bool(REGB1)) {
-    /* ./compiling//compiling_icode.nit:1233 */
+    /* compiling/compiling_icode.nit:1274 */
      if (!once_value_5) {
        fra.me.REG[0] = BOX_NativeString("return;");
        REGB1 = TAG_Int(7);
@@ -16158,7 +17776,7 @@ val_t compiling___compiling_icode___IClosureDef___compile_closure(val_t p0, val_
      fra.me.REG[0] = fra.me.REG[0];
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    } else {
-    /* ./compiling//compiling_icode.nit:1235 */
+    /* compiling/compiling_icode.nit:1276 */
      REGB1 = TAG_Int(3);
      fra.me.REG[0] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
      if (!once_value_6) {
@@ -16183,9 +17801,9 @@ val_t compiling___compiling_icode___IClosureDef___compile_closure(val_t p0, val_
      fra.me.REG[0] = CALL_standard___string___Object___to_s(fra.me.REG[0])(fra.me.REG[0]);
      CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
    }
-  /* ./compiling//compiling_icode.nit:1237 */
+  /* compiling/compiling_icode.nit:1278 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___unindent(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./compiling//compiling_icode.nit:1238 */
+  /* compiling/compiling_icode.nit:1279 */
    if (!once_value_8) {
      fra.me.REG[0] = BOX_NativeString("}");
      REGB1 = TAG_Int(1);
@@ -16195,15 +17813,15 @@ val_t compiling___compiling_icode___IClosureDef___compile_closure(val_t p0, val_
    } else fra.me.REG[0] = once_value_8;
    fra.me.REG[0] = fra.me.REG[0];
    CALL_compiling___compiling_icode___I2CCompilerVisitor___add_instr(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./compiling//compiling_icode.nit:1241 */
+  /* compiling/compiling_icode.nit:1282 */
    CALL_compiling___compiling_base___CompilerVisitor___writer__eq(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[5]);
-  /* ./compiling//compiling_icode.nit:1242 */
+  /* compiling/compiling_icode.nit:1283 */
    CALL_compiling___compiling_base___CompilerVisitor___decl_writer__eq(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
-  /* ./compiling//compiling_icode.nit:1243 */
+  /* compiling/compiling_icode.nit:1284 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___closure__eq(fra.me.REG[1])(fra.me.REG[1], REGB0);
-  /* ./compiling//compiling_icode.nit:1244 */
+  /* compiling/compiling_icode.nit:1285 */
    CALL_compiling___compiling_icode___I2CCompilerVisitor___local_labels__eq(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./compiling//compiling_icode.nit:1245 */
+  /* compiling/compiling_icode.nit:1286 */
    REGB0 = TAG_Int(3);
    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
    if (!once_value_9) {