c_src : Regenerated c_src to prevent use of String contructors

[nit.git] / c_src / opts._sep.c

diff --git a/c_src/opts._sep.c b/c_src/opts._sep.c
index 3c407b2..23ebd5a 100644 (file)
--- a/c_src/opts._sep.c
+++ b/c_src/opts._sep.c
@@ -1,5 +1,6 @@
 /* This C file is generated by NIT to compile module opts. */
 #include "opts._sep.h"
+static const char LOCATE_opts___Option___names[] = "opts::Option::names";
 val_t opts___Option___names(val_t p0){
   struct {struct stack_frame_t me;} fra;
   val_t REGB0;
@@ -13,7 +14,7 @@ val_t opts___Option___names(val_t p0){
   fra.me.nitni_local_ref_head = NULL;
   fra.me.REG[0] = NIT_NULL;
   fra.me.REG[0] = p0;
-  /* ./../lib/opts.nit:19 */
+  /* ../lib/opts.nit:19 */
   REGB0 = TAG_Bool(ATTR_opts___Option____names(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
@@ -23,6 +24,7 @@ val_t opts___Option___names(val_t p0){
   stack_frame_head = fra.me.prev;
   return fra.me.REG[0];
 }
+static const char LOCATE_opts___Option___helptext[] = "opts::Option::helptext";
 val_t opts___Option___helptext(val_t p0){
   struct {struct stack_frame_t me;} fra;
   val_t REGB0;
@@ -36,7 +38,7 @@ val_t opts___Option___helptext(val_t p0){
   fra.me.nitni_local_ref_head = NULL;
   fra.me.REG[0] = NIT_NULL;
   fra.me.REG[0] = p0;
-  /* ./../lib/opts.nit:25 */
+  /* ../lib/opts.nit:25 */
   REGB0 = TAG_Bool(ATTR_opts___Option____helptext(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
@@ -46,36 +48,62 @@ val_t opts___Option___helptext(val_t p0){
   stack_frame_head = fra.me.prev;
   return fra.me.REG[0];
 }
-val_t opts___Option___mandatory(val_t p0){
+static const char LOCATE_opts___Option___errors[] = "opts::Option::errors";
+val_t opts___Option___errors(val_t p0){
   struct {struct stack_frame_t me;} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
   fra.me.line = 28;
+  fra.me.meth = LOCATE_opts___Option___errors;
+  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;
+  /* ../lib/opts.nit:28 */
+  REGB0 = TAG_Bool(ATTR_opts___Option____errors(fra.me.REG[0])!=NIT_NULL);
+  if (UNTAG_Bool(REGB0)) {
+  } else {
+    nit_abort("Uninitialized attribute %s", "_errors", LOCATE_opts, 28);
+  }
+  fra.me.REG[0] = ATTR_opts___Option____errors(fra.me.REG[0]);
+  stack_frame_head = fra.me.prev;
+  return fra.me.REG[0];
+}
+static const char LOCATE_opts___Option___mandatory[] = "opts::Option::mandatory";
+val_t opts___Option___mandatory(val_t p0){
+  struct {struct stack_frame_t me;} fra;
+  val_t REGB0;
+  val_t tmp;
+  fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
+  fra.me.file = LOCATE_opts;
+  fra.me.line = 31;
   fra.me.meth = LOCATE_opts___Option___mandatory;
   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;
-  /* ./../lib/opts.nit:28 */
+  /* ../lib/opts.nit:31 */
   REGB0 = TAG_Bool(ATTR_opts___Option____mandatory(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_mandatory", LOCATE_opts, 28);
+    nit_abort("Uninitialized attribute %s", "_mandatory", LOCATE_opts, 31);
   }
   REGB0 = ATTR_opts___Option____mandatory(fra.me.REG[0]);
   stack_frame_head = fra.me.prev;
   return REGB0;
 }
+static const char LOCATE_opts___Option___mandatory__eq[] = "opts::Option::mandatory=";
 void opts___Option___mandatory__eq(val_t p0, val_t p1){
   struct {struct stack_frame_t me;} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 28;
+  fra.me.line = 31;
   fra.me.meth = LOCATE_opts___Option___mandatory__eq;
   fra.me.has_broke = 0;
   fra.me.REG_size = 1;
@@ -83,17 +111,42 @@ void opts___Option___mandatory__eq(val_t p0, val_t p1){
   fra.me.REG[0] = NIT_NULL;
   fra.me.REG[0] = p0;
   REGB0 = p1;
-  /* ./../lib/opts.nit:28 */
+  /* ../lib/opts.nit:31 */
   ATTR_opts___Option____mandatory(fra.me.REG[0]) = REGB0;
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___Option___read[] = "opts::Option::read";
+val_t opts___Option___read(val_t p0){
+  struct {struct stack_frame_t me;} fra;
+  val_t REGB0;
+  val_t tmp;
+  fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
+  fra.me.file = LOCATE_opts;
+  fra.me.line = 34;
+  fra.me.meth = LOCATE_opts___Option___read;
+  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;
+  /* ../lib/opts.nit:34 */
+  REGB0 = TAG_Bool(ATTR_opts___Option____read(fra.me.REG[0])!=NIT_NULL);
+  if (UNTAG_Bool(REGB0)) {
+  } else {
+    nit_abort("Uninitialized attribute %s", "_read", LOCATE_opts, 34);
+  }
+  REGB0 = ATTR_opts___Option____read(fra.me.REG[0]);
+  stack_frame_head = fra.me.prev;
+  return REGB0;
+}
+static const char LOCATE_opts___Option___value__eq[] = "opts::Option::value=";
 void opts___Option___value__eq(val_t p0, val_t p1){
   struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 31;
+  fra.me.line = 37;
   fra.me.meth = LOCATE_opts___Option___value__eq;
   fra.me.has_broke = 0;
   fra.me.REG_size = 2;
@@ -102,18 +155,19 @@ void opts___Option___value__eq(val_t p0, val_t p1){
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:31 */
+  /* ../lib/opts.nit:37 */
   ATTR_opts___Option____value(fra.me.REG[0]) = fra.me.REG[1];
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___Option___value[] = "opts::Option::value";
 val_t opts___Option___value(val_t p0){
   struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 34;
+  fra.me.line = 40;
   fra.me.meth = LOCATE_opts___Option___value;
   fra.me.has_broke = 0;
   fra.me.REG_size = 2;
@@ -121,43 +175,45 @@ val_t opts___Option___value(val_t p0){
   fra.me.REG[0] = NIT_NULL;
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[0] = p0;
-  /* ./../lib/opts.nit:34 */
+  /* ../lib/opts.nit:40 */
   fra.me.REG[1] = fra.me.REG[0];
-  /* ./../lib/opts.nit:35 */
+  /* ../lib/opts.nit:41 */
   fra.me.REG[1] = ATTR_opts___Option____value(fra.me.REG[1]);
   REGB0 = TAG_Bool((fra.me.REG[1]==NIT_NULL) || VAL_ISA(fra.me.REG[1], VTCOLOR_opts___Option___VALUE(fra.me.REG[0]), VTID_opts___Option___VALUE(fra.me.REG[0]))) /*cast VALUE*/;
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Cast failed", NULL, LOCATE_opts, 35);
+    nit_abort("Cast failed", NULL, LOCATE_opts, 41);
   }
   goto label1;
   label1: while(0);
   stack_frame_head = fra.me.prev;
   return fra.me.REG[1];
 }
+static const char LOCATE_opts___Option___default_value[] = "opts::Option::default_value";
 val_t opts___Option___default_value(val_t p0){
   struct {struct stack_frame_t me;} fra;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 37;
+  fra.me.line = 43;
   fra.me.meth = LOCATE_opts___Option___default_value;
   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;
-  /* ./../lib/opts.nit:37 */
+  /* ../lib/opts.nit:43 */
   fra.me.REG[0] = ATTR_opts___Option____default_value(fra.me.REG[0]);
   stack_frame_head = fra.me.prev;
   return fra.me.REG[0];
 }
+static const char LOCATE_opts___Option___default_value__eq[] = "opts::Option::default_value=";
 void opts___Option___default_value__eq(val_t p0, val_t p1){
   struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 37;
+  fra.me.line = 43;
   fra.me.meth = LOCATE_opts___Option___default_value__eq;
   fra.me.has_broke = 0;
   fra.me.REG_size = 2;
@@ -166,11 +222,12 @@ void opts___Option___default_value__eq(val_t p0, val_t p1){
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:37 */
+  /* ../lib/opts.nit:43 */
   ATTR_opts___Option____default_value(fra.me.REG[0]) = fra.me.REG[1];
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___Option___init_opt[] = "opts::Option::init_opt";
 void opts___Option___init_opt(val_t p0, val_t p1, val_t p2, val_t p3, int* init_table){
   int itpos0 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___Option].i;
   struct {struct stack_frame_t me; val_t MORE_REG[4];} fra;
@@ -180,7 +237,7 @@ void opts___Option___init_opt(val_t p0, val_t p1, val_t p2, val_t p3, int* init_
   if (init_table[itpos0]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 40;
+  fra.me.line = 46;
   fra.me.meth = LOCATE_opts___Option___init_opt;
   fra.me.has_broke = 0;
   fra.me.REG_size = 5;
@@ -194,13 +251,13 @@ void opts___Option___init_opt(val_t p0, val_t p1, val_t p2, val_t p3, int* init_
   fra.me.REG[1] = p1;
   fra.me.REG[2] = p2;
   fra.me.REG[3] = p3;
-  /* ./../lib/opts.nit:43 */
+  /* ../lib/opts.nit:49 */
   REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
     REGB1 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
     if (UNTAG_Bool(REGB1)) {
-      REGB1 = TAG_Bool(false);
+      REGB1 = TAG_Bool(0);
       REGB0 = REGB1;
     } else {
       REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[3])(fra.me.REG[3], NIT_NULL);
@@ -208,38 +265,45 @@ void opts___Option___init_opt(val_t p0, val_t p1, val_t p2, val_t p3, int* init_
     }
   }
   if (UNTAG_Bool(REGB0)) {
-    /* ./../lib/opts.nit:44 */
+    /* ../lib/opts.nit:50 */
     fra.me.REG[4] = NEW_Array_standard___collection___array___Array___init();
     ATTR_opts___Option____names(fra.me.REG[0]) = fra.me.REG[4];
   } else {
-    /* ./../lib/opts.nit:46 */
+    /* ../lib/opts.nit:52 */
     REGB0 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
     if (UNTAG_Bool(REGB0)) {
-      nit_abort("Reciever is null", NULL, LOCATE_opts, 46);
+      nit_abort("Reciever is null", NULL, LOCATE_opts, 52);
     }
     fra.me.REG[3] = CALL_standard___collection___array___Collection___to_a(fra.me.REG[3])(fra.me.REG[3]);
     ATTR_opts___Option____names(fra.me.REG[0]) = fra.me.REG[3];
   }
-  /* ./../lib/opts.nit:48 */
+  /* ../lib/opts.nit:54 */
   ATTR_opts___Option____helptext(fra.me.REG[0]) = fra.me.REG[1];
-  /* ./../lib/opts.nit:49 */
-  REGB0 = TAG_Bool(false);
+  /* ../lib/opts.nit:55 */
+  REGB0 = TAG_Bool(0);
   ATTR_opts___Option____mandatory(fra.me.REG[0]) = REGB0;
-  /* ./../lib/opts.nit:50 */
+  /* ../lib/opts.nit:56 */
+  REGB0 = TAG_Bool(0);
+  ATTR_opts___Option____read(fra.me.REG[0]) = REGB0;
+  /* ../lib/opts.nit:57 */
   ATTR_opts___Option____default_value(fra.me.REG[0]) = fra.me.REG[2];
-  /* ./../lib/opts.nit:51 */
+  /* ../lib/opts.nit:58 */
   ATTR_opts___Option____value(fra.me.REG[0]) = fra.me.REG[2];
+  /* ../lib/opts.nit:59 */
+  fra.me.REG[2] = NEW_Array_standard___collection___array___Array___init();
+  ATTR_opts___Option____errors(fra.me.REG[0]) = fra.me.REG[2];
   stack_frame_head = fra.me.prev;
   init_table[itpos0] = 1;
   return;
 }
+static const char LOCATE_opts___Option___add_aliases[] = "opts::Option::add_aliases";
 void opts___Option___add_aliases(val_t p0, val_t p1){
   struct {struct stack_frame_t me; val_t MORE_REG[2];} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 54;
+  fra.me.line = 62;
   fra.me.meth = LOCATE_opts___Option___add_aliases;
   fra.me.has_broke = 0;
   fra.me.REG_size = 3;
@@ -249,38 +313,39 @@ void opts___Option___add_aliases(val_t p0, val_t p1){
   fra.me.REG[2] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:54 */
+  /* ../lib/opts.nit:62 */
   fra.me.REG[2] = fra.me.REG[0];
   REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[1], COLOR_standard___collection___array___Array, ID_standard___collection___array___Array)) /*cast Array[String]*/;
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Cast failed", NULL, LOCATE_opts, 54);
+    nit_abort("Cast failed", NULL, LOCATE_opts, 62);
   }
-  /* ./../lib/opts.nit:55 */
+  /* ../lib/opts.nit:63 */
   REGB0 = TAG_Bool(ATTR_opts___Option____names(fra.me.REG[2])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_names", LOCATE_opts, 55);
+    nit_abort("Uninitialized attribute %s", "_names", LOCATE_opts, 63);
   }
   fra.me.REG[2] = ATTR_opts___Option____names(fra.me.REG[2]);
   CALL_standard___collection___abstract_collection___SimpleCollection___add_all(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___Option___to_s[] = "opts::Option::(string::Object::to_s)";
 val_t opts___Option___to_s(val_t p0){
   struct {struct stack_frame_t me;} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 57;
+  fra.me.line = 65;
   fra.me.meth = LOCATE_opts___Option___to_s;
   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;
-  /* ./../lib/opts.nit:58 */
+  /* ../lib/opts.nit:66 */
   REGB0 = TAG_Int(2);
   fra.me.REG[0] = CALL_opts___Option___pretty(fra.me.REG[0])(fra.me.REG[0], REGB0);
   goto label1;
@@ -288,6 +353,7 @@ val_t opts___Option___to_s(val_t p0){
   stack_frame_head = fra.me.prev;
   return fra.me.REG[0];
 }
+static const char LOCATE_opts___Option___pretty[] = "opts::Option::pretty";
 val_t opts___Option___pretty(val_t p0, val_t p1){
   struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
   val_t REGB0;
@@ -300,7 +366,7 @@ val_t opts___Option___pretty(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_opts;
-  fra.me.line = 60;
+  fra.me.line = 68;
   fra.me.meth = LOCATE_opts___Option___pretty;
   fra.me.has_broke = 0;
   fra.me.REG_size = 4;
@@ -311,67 +377,67 @@ val_t opts___Option___pretty(val_t p0, val_t p1){
   fra.me.REG[3] = NIT_NULL;
   fra.me.REG[0] = p0;
   REGB0 = p1;
-  /* ./../lib/opts.nit:63 */
+  /* ../lib/opts.nit:71 */
   if (!once_value_1) {
     fra.me.REG[1] = BOX_NativeString("  ");
     REGB1 = TAG_Int(2);
-    fra.me.REG[1] = NEW_String_standard___string___String___with_native(fra.me.REG[1], REGB1);
+    fra.me.REG[1] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[1])(fra.me.REG[1], REGB1);
     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];
   fra.me.REG[1] = NEW_Buffer_standard___string___Buffer___from(fra.me.REG[1]);
-  /* ./../lib/opts.nit:64 */
+  /* ../lib/opts.nit:72 */
   REGB1 = TAG_Bool(ATTR_opts___Option____names(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB1)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_names", LOCATE_opts, 64);
+    nit_abort("Uninitialized attribute %s", "_names", LOCATE_opts, 72);
   }
   fra.me.REG[2] = ATTR_opts___Option____names(fra.me.REG[0]);
   if (!once_value_2) {
     fra.me.REG[3] = BOX_NativeString(", ");
     REGB1 = TAG_Int(2);
-    fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB1);
+    fra.me.REG[3] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[3])(fra.me.REG[3], REGB1);
     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];
   fra.me.REG[3] = CALL_standard___string___Collection___join(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
   CALL_standard___collection___abstract_collection___Sequence___append(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./../lib/opts.nit:65 */
+  /* ../lib/opts.nit:73 */
   if (!once_value_3) {
     fra.me.REG[3] = BOX_NativeString("  ");
     REGB1 = TAG_Int(2);
-    fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB1);
+    fra.me.REG[3] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[3])(fra.me.REG[3], REGB1);
     once_value_3 = fra.me.REG[3];
     register_static_object(&once_value_3);
   } else fra.me.REG[3] = once_value_3;
   fra.me.REG[3] = fra.me.REG[3];
   CALL_standard___collection___abstract_collection___Sequence___append(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
-  /* ./../lib/standard//collection//array.nit:24 */
+  /* ../lib/standard/collection/array.nit:24 */
   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, 24);
   }
   REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1]);
-  /* ./../lib/standard//kernel.nit:237 */
+  /* ../lib/standard/kernel.nit:247 */
   REGB1 = TAG_Int(UNTAG_Int(REGB0)-UNTAG_Int(REGB1));
-  /* ./../lib/opts.nit:67 */
+  /* ../lib/opts.nit:75 */
   REGB0 = TAG_Int(0);
   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:234 */
+  /* ../lib/standard/kernel.nit:244 */
   REGB0 = TAG_Bool(UNTAG_Int(REGB1)>UNTAG_Int(REGB0));
-  /* ./../lib/opts.nit:67 */
+  /* ../lib/opts.nit:75 */
   if (UNTAG_Bool(REGB0)) {
     if (!once_value_4) {
       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);
+      fra.me.REG[3] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[3])(fra.me.REG[3], REGB0);
       once_value_4 = fra.me.REG[3];
       register_static_object(&once_value_4);
     } else fra.me.REG[3] = once_value_4;
@@ -379,16 +445,17 @@ val_t opts___Option___pretty(val_t p0, val_t p1){
     fra.me.REG[3] = CALL_standard___string___String_____star(fra.me.REG[3])(fra.me.REG[3], REGB1);
     CALL_standard___collection___abstract_collection___Sequence___append(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
   }
-  /* ./../lib/opts.nit:68 */
+  /* ../lib/opts.nit:76 */
   fra.me.REG[0] = CALL_opts___Option___helptext(fra.me.REG[0])(fra.me.REG[0]);
   CALL_standard___collection___abstract_collection___Sequence___append(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
-  /* ./../lib/opts.nit:70 */
+  /* ../lib/opts.nit:78 */
   fra.me.REG[1] = CALL_standard___string___Object___to_s(fra.me.REG[1])(fra.me.REG[1]);
   goto label5;
   label5: while(0);
   stack_frame_head = fra.me.prev;
   return fra.me.REG[1];
 }
+static const char LOCATE_opts___Option___pretty_default[] = "opts::Option::pretty_default";
 val_t opts___Option___pretty_default(val_t p0){
   struct {struct stack_frame_t me; val_t MORE_REG[2];} fra;
   val_t REGB0;
@@ -399,7 +466,7 @@ val_t opts___Option___pretty_default(val_t p0){
   static val_t once_value_4; /* Once value */
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 73;
+  fra.me.line = 81;
   fra.me.meth = LOCATE_opts___Option___pretty_default;
   fra.me.has_broke = 0;
   fra.me.REG_size = 3;
@@ -408,15 +475,15 @@ val_t opts___Option___pretty_default(val_t p0){
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[2] = NIT_NULL;
   fra.me.REG[0] = p0;
-  /* ./../lib/opts.nit:75 */
+  /* ../lib/opts.nit:83 */
   fra.me.REG[0] = CALL_opts___Option___default_value(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./../lib/opts.nit:76 */
+  /* ../lib/opts.nit:84 */
   REGB0 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
     REGB1 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
     if (UNTAG_Bool(REGB1)) {
-      REGB1 = TAG_Bool(false);
+      REGB1 = TAG_Bool(0);
       REGB0 = REGB1;
     } else {
       REGB1 = CALL_standard___kernel___Object_____eqeq(fra.me.REG[0])(fra.me.REG[0], NIT_NULL);
@@ -430,7 +497,7 @@ val_t opts___Option___pretty_default(val_t p0){
     if (!once_value_1) {
       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);
+      fra.me.REG[2] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[2])(fra.me.REG[2], REGB0);
       once_value_1 = fra.me.REG[2];
       register_static_object(&once_value_1);
     } else fra.me.REG[2] = once_value_1;
@@ -441,7 +508,7 @@ val_t opts___Option___pretty_default(val_t p0){
     if (!once_value_2) {
       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);
+      fra.me.REG[0] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[0])(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;
@@ -450,11 +517,11 @@ val_t opts___Option___pretty_default(val_t p0){
     fra.me.REG[1] = CALL_standard___string___Object___to_s(fra.me.REG[1])(fra.me.REG[1]);
     goto label3;
   }
-  /* ./../lib/opts.nit:77 */
+  /* ../lib/opts.nit:85 */
   if (!once_value_4) {
     fra.me.REG[0] = BOX_NativeString("");
     REGB0 = TAG_Int(0);
-    fra.me.REG[0] = NEW_String_standard___string___String___with_native(fra.me.REG[0], REGB0);
+    fra.me.REG[0] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[0])(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;
@@ -465,21 +532,29 @@ val_t opts___Option___pretty_default(val_t p0){
   stack_frame_head = fra.me.prev;
   return fra.me.REG[1];
 }
+static const char LOCATE_opts___Option___read_param[] = "opts::Option::read_param";
 void opts___Option___read_param(val_t p0, val_t p1){
-  struct {struct stack_frame_t me;} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
+  val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 80;
+  fra.me.line = 88;
   fra.me.meth = LOCATE_opts___Option___read_param;
   fra.me.has_broke = 0;
-  fra.me.REG_size = 0;
+  fra.me.REG_size = 2;
   fra.me.nitni_local_ref_head = NULL;
-  /* ./../lib/opts.nit:80 */
-  nit_abort("Deferred method called", NULL, LOCATE_opts, 80);
+  fra.me.REG[0] = NIT_NULL;
+  fra.me.REG[1] = NIT_NULL;
+  fra.me.REG[0] = p0;
+  fra.me.REG[1] = p1;
+  /* ../lib/opts.nit:91 */
+  REGB0 = TAG_Bool(1);
+  ATTR_opts___Option____read(fra.me.REG[0]) = REGB0;
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___OptionText___init[] = "opts::OptionText::init";
 void opts___OptionText___init(val_t p0, val_t p1, int* init_table){
   int itpos1 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___OptionText].i;
   struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
@@ -487,7 +562,7 @@ void opts___OptionText___init(val_t p0, val_t p1, int* init_table){
   if (init_table[itpos1]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 86;
+  fra.me.line = 97;
   fra.me.meth = LOCATE_opts___OptionText___init;
   fra.me.has_broke = 0;
   fra.me.REG_size = 2;
@@ -496,19 +571,20 @@ void opts___OptionText___init(val_t p0, val_t p1, int* init_table){
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:86 */
+  /* ../lib/opts.nit:97 */
   CALL_opts___Option___init_opt(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1], NIT_NULL, NIT_NULL, init_table);
   stack_frame_head = fra.me.prev;
   init_table[itpos1] = 1;
   return;
 }
+static const char LOCATE_opts___OptionText___pretty[] = "opts::OptionText::(opts::Option::pretty)";
 val_t opts___OptionText___pretty(val_t p0, val_t p1){
   struct {struct stack_frame_t me;} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 88;
+  fra.me.line = 99;
   fra.me.meth = LOCATE_opts___OptionText___pretty;
   fra.me.has_broke = 0;
   fra.me.REG_size = 1;
@@ -516,32 +592,34 @@ val_t opts___OptionText___pretty(val_t p0, val_t p1){
   fra.me.REG[0] = NIT_NULL;
   fra.me.REG[0] = p0;
   REGB0 = p1;
-  /* ./../lib/opts.nit:88 */
+  /* ../lib/opts.nit:99 */
   fra.me.REG[0] = CALL_standard___string___Object___to_s(fra.me.REG[0])(fra.me.REG[0]);
   goto label1;
   label1: while(0);
   stack_frame_head = fra.me.prev;
   return fra.me.REG[0];
 }
+static const char LOCATE_opts___OptionText___to_s[] = "opts::OptionText::(string::Object::to_s)";
 val_t opts___OptionText___to_s(val_t p0){
   struct {struct stack_frame_t me;} fra;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 90;
+  fra.me.line = 101;
   fra.me.meth = LOCATE_opts___OptionText___to_s;
   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;
-  /* ./../lib/opts.nit:90 */
+  /* ../lib/opts.nit:101 */
   fra.me.REG[0] = CALL_opts___Option___helptext(fra.me.REG[0])(fra.me.REG[0]);
   goto label1;
   label1: while(0);
   stack_frame_head = fra.me.prev;
   return fra.me.REG[0];
 }
+static const char LOCATE_opts___OptionBool___init[] = "opts::OptionBool::init";
 void opts___OptionBool___init(val_t p0, val_t p1, val_t p2, int* init_table){
   int itpos2 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___OptionBool].i;
   struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
@@ -550,7 +628,7 @@ void opts___OptionBool___init(val_t p0, val_t p1, val_t p2, int* init_table){
   if (init_table[itpos2]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 97;
+  fra.me.line = 108;
   fra.me.meth = LOCATE_opts___OptionBool___init;
   fra.me.has_broke = 0;
   fra.me.REG_size = 4;
@@ -562,40 +640,47 @@ void opts___OptionBool___init(val_t p0, val_t p1, val_t p2, int* init_table){
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
   fra.me.REG[2] = p2;
-  /* ./../lib/opts.nit:97 */
+  /* ../lib/opts.nit:108 */
   fra.me.REG[3] = fra.me.REG[0];
   REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[2], COLOR_standard___collection___array___Array, ID_standard___collection___array___Array)) /*cast Array[String]*/;
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Cast failed", NULL, LOCATE_opts, 97);
+    nit_abort("Cast failed", NULL, LOCATE_opts, 108);
   }
-  REGB0 = TAG_Bool(false);
+  REGB0 = TAG_Bool(0);
   CALL_opts___Option___init_opt(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1], REGB0, fra.me.REG[2], init_table);
   stack_frame_head = fra.me.prev;
   init_table[itpos2] = 1;
   return;
 }
+static const char LOCATE_opts___OptionBool___read_param[] = "opts::OptionBool::(opts::Option::read_param)";
 void opts___OptionBool___read_param(val_t p0, val_t p1){
-  struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[2];} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 99;
+  fra.me.line = 110;
   fra.me.meth = LOCATE_opts___OptionBool___read_param;
   fra.me.has_broke = 0;
-  fra.me.REG_size = 2;
+  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;
-  /* ./../lib/opts.nit:99 */
-  REGB0 = TAG_Bool(true);
-  CALL_opts___Option___value__eq(fra.me.REG[0])(fra.me.REG[0], REGB0);
+  /* ../lib/opts.nit:110 */
+  fra.me.REG[2] = fra.me.REG[0];
+  /* ../lib/opts.nit:112 */
+  CALL_SUPER_opts___OptionBool___read_param(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
+  /* ../lib/opts.nit:113 */
+  REGB0 = TAG_Bool(1);
+  CALL_opts___Option___value__eq(fra.me.REG[2])(fra.me.REG[2], REGB0);
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___OptionCount___init[] = "opts::OptionCount::init";
 void opts___OptionCount___init(val_t p0, val_t p1, val_t p2, int* init_table){
   int itpos3 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___OptionCount].i;
   struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
@@ -604,7 +689,7 @@ void opts___OptionCount___init(val_t p0, val_t p1, val_t p2, int* init_table){
   if (init_table[itpos3]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 106;
+  fra.me.line = 121;
   fra.me.meth = LOCATE_opts___OptionCount___init;
   fra.me.has_broke = 0;
   fra.me.REG_size = 4;
@@ -616,12 +701,12 @@ void opts___OptionCount___init(val_t p0, val_t p1, val_t p2, int* init_table){
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
   fra.me.REG[2] = p2;
-  /* ./../lib/opts.nit:106 */
+  /* ../lib/opts.nit:121 */
   fra.me.REG[3] = fra.me.REG[0];
   REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[2], COLOR_standard___collection___array___Array, ID_standard___collection___array___Array)) /*cast Array[String]*/;
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Cast failed", NULL, LOCATE_opts, 106);
+    nit_abort("Cast failed", NULL, LOCATE_opts, 121);
   }
   REGB0 = TAG_Int(0);
   CALL_opts___Option___init_opt(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1], REGB0, fra.me.REG[2], init_table);
@@ -629,101 +714,241 @@ void opts___OptionCount___init(val_t p0, val_t p1, val_t p2, int* init_table){
   init_table[itpos3] = 1;
   return;
 }
+static const char LOCATE_opts___OptionCount___read_param[] = "opts::OptionCount::(opts::Option::read_param)";
 void opts___OptionCount___read_param(val_t p0, val_t p1){
-  struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[2];} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 108;
+  fra.me.line = 123;
   fra.me.meth = LOCATE_opts___OptionCount___read_param;
   fra.me.has_broke = 0;
-  fra.me.REG_size = 2;
+  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;
-  /* ./../lib/opts.nit:108 */
-  fra.me.REG[1] = CALL_opts___Option___value(fra.me.REG[0])(fra.me.REG[0]);
+  /* ../lib/opts.nit:123 */
+  fra.me.REG[2] = fra.me.REG[0];
+  /* ../lib/opts.nit:125 */
+  CALL_SUPER_opts___OptionCount___read_param(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
+  /* ../lib/opts.nit:126 */
+  fra.me.REG[1] = CALL_opts___Option___value(fra.me.REG[2])(fra.me.REG[2]);
   REGB0 = TAG_Int(1);
-  /* ./../lib/standard//kernel.nit:235 */
+  /* ../lib/standard/kernel.nit:245 */
   REGB0 = TAG_Int(UNTAG_Int(fra.me.REG[1])+UNTAG_Int(REGB0));
-  /* ./../lib/opts.nit:108 */
-  CALL_opts___Option___value__eq(fra.me.REG[0])(fra.me.REG[0], REGB0);
+  /* ../lib/opts.nit:126 */
+  CALL_opts___Option___value__eq(fra.me.REG[2])(fra.me.REG[2], REGB0);
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___OptionParameter___convert[] = "opts::OptionParameter::convert";
 val_t opts___OptionParameter___convert(val_t p0, val_t p1){
   struct {struct stack_frame_t me;} fra;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 114;
+  fra.me.line = 133;
   fra.me.meth = LOCATE_opts___OptionParameter___convert;
   fra.me.has_broke = 0;
   fra.me.REG_size = 0;
   fra.me.nitni_local_ref_head = NULL;
-  /* ./../lib/opts.nit:114 */
-  nit_abort("Deferred method called", NULL, LOCATE_opts, 114);
+  /* ../lib/opts.nit:133 */
+  nit_abort("Deferred method called", NULL, LOCATE_opts, 133);
   stack_frame_head = fra.me.prev;
   return NIT_NULL;
 }
+static const char LOCATE_opts___OptionParameter___parameter_mandatory[] = "opts::OptionParameter::parameter_mandatory";
+val_t opts___OptionParameter___parameter_mandatory(val_t p0){
+  struct {struct stack_frame_t me;} fra;
+  val_t REGB0;
+  val_t tmp;
+  fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
+  fra.me.file = LOCATE_opts;
+  fra.me.line = 135;
+  fra.me.meth = LOCATE_opts___OptionParameter___parameter_mandatory;
+  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;
+  /* ../lib/opts.nit:135 */
+  REGB0 = TAG_Bool(ATTR_opts___OptionParameter____parameter_mandatory(fra.me.REG[0])!=NIT_NULL);
+  if (UNTAG_Bool(REGB0)) {
+  } else {
+    nit_abort("Uninitialized attribute %s", "_parameter_mandatory", LOCATE_opts, 135);
+  }
+  REGB0 = ATTR_opts___OptionParameter____parameter_mandatory(fra.me.REG[0]);
+  stack_frame_head = fra.me.prev;
+  return REGB0;
+}
+static const char LOCATE_opts___OptionParameter___parameter_mandatory__eq[] = "opts::OptionParameter::parameter_mandatory=";
+void opts___OptionParameter___parameter_mandatory__eq(val_t p0, val_t p1){
+  struct {struct stack_frame_t me;} fra;
+  val_t REGB0;
+  val_t tmp;
+  fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
+  fra.me.file = LOCATE_opts;
+  fra.me.line = 135;
+  fra.me.meth = LOCATE_opts___OptionParameter___parameter_mandatory__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;
+  /* ../lib/opts.nit:135 */
+  ATTR_opts___OptionParameter____parameter_mandatory(fra.me.REG[0]) = REGB0;
+  stack_frame_head = fra.me.prev;
+  return;
+}
+static const char LOCATE_opts___OptionParameter___read_param[] = "opts::OptionParameter::(opts::Option::read_param)";
 void opts___OptionParameter___read_param(val_t p0, val_t p1){
-  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 REGB1;
+  val_t REGB2;
   val_t tmp;
+      static val_t once_value_1; /* Once value */
+      static val_t once_value_2; /* Once value */
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 116;
+  fra.me.line = 138;
   fra.me.meth = LOCATE_opts___OptionParameter___read_param;
   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;
-  /* ./../lib/opts.nit:118 */
-  REGB0 = CALL_standard___collection___abstract_collection___Iterator___is_ok(fra.me.REG[1])(fra.me.REG[1]);
+  /* ../lib/opts.nit:138 */
+  fra.me.REG[2] = fra.me.REG[0];
+  fra.me.REG[3] = fra.me.REG[1];
+  /* ../lib/opts.nit:140 */
+  CALL_SUPER_opts___OptionParameter___read_param(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
+  /* ../lib/opts.nit:141 */
+  REGB0 = CALL_standard___collection___abstract_collection___Iterator___is_ok(fra.me.REG[3])(fra.me.REG[3]);
   if (UNTAG_Bool(REGB0)) {
-    /* ./../lib/opts.nit:119 */
-    fra.me.REG[2] = CALL_standard___collection___abstract_collection___Iterator___item(fra.me.REG[1])(fra.me.REG[1]);
-    fra.me.REG[2] = CALL_opts___OptionParameter___convert(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[2]);
-    CALL_opts___Option___value__eq(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[2]);
-    /* ./../lib/opts.nit:120 */
-    CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[1])(fra.me.REG[1]);
+    fra.me.REG[1] = CALL_standard___collection___abstract_collection___Iterator___item(fra.me.REG[3])(fra.me.REG[3]);
+    REGB0 = TAG_Bool(fra.me.REG[1]==NIT_NULL);
+    if (UNTAG_Bool(REGB0)) {
+      nit_abort("Reciever is null", NULL, LOCATE_opts, 141);
+    }
+    fra.me.REG[1] = CALL_standard___collection___abstract_collection___Collection___first(fra.me.REG[1])(fra.me.REG[1]);
+    REGB0 = TAG_Char('-');
+    REGB1 = TAG_Bool(IS_EQUAL_ON(REGB0,fra.me.REG[1]));
+    if (UNTAG_Bool(REGB1)) {
+    } else {
+      REGB2 = TAG_Bool(fra.me.REG[1]==NIT_NULL);
+      if (UNTAG_Bool(REGB2)) {
+        REGB2 = TAG_Bool(0);
+        REGB1 = REGB2;
+      } else {
+        /* ../lib/standard/kernel.nit:434 */
+        REGB0 = TAG_Bool((fra.me.REG[1])==(REGB0));
+        /* ../lib/opts.nit:141 */
+        REGB1 = REGB0;
+      }
+    }
+    REGB1 = TAG_Bool(!UNTAG_Bool(REGB1));
+  } else {
+    REGB0 = TAG_Bool(0);
+    REGB1 = REGB0;
+  }
+  if (UNTAG_Bool(REGB1)) {
+    /* ../lib/opts.nit:142 */
+    fra.me.REG[1] = CALL_standard___collection___abstract_collection___Iterator___item(fra.me.REG[3])(fra.me.REG[3]);
+    fra.me.REG[1] = CALL_opts___OptionParameter___convert(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+    CALL_opts___Option___value__eq(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+    /* ../lib/opts.nit:143 */
+    CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[3])(fra.me.REG[3]);
+  } else {
+    /* ../lib/opts.nit:145 */
+    REGB1 = TAG_Bool(ATTR_opts___OptionParameter____parameter_mandatory(fra.me.REG[2])!=NIT_NULL);
+    if (UNTAG_Bool(REGB1)) {
+    } else {
+      nit_abort("Uninitialized attribute %s", "_parameter_mandatory", LOCATE_opts, 145);
+    }
+    REGB1 = ATTR_opts___OptionParameter____parameter_mandatory(fra.me.REG[2]);
+    if (UNTAG_Bool(REGB1)) {
+      /* ../lib/opts.nit:146 */
+      REGB1 = TAG_Bool(ATTR_opts___Option____errors(fra.me.REG[2])!=NIT_NULL);
+      if (UNTAG_Bool(REGB1)) {
+      } else {
+        nit_abort("Uninitialized attribute %s", "_errors", LOCATE_opts, 146);
+      }
+      fra.me.REG[3] = ATTR_opts___Option____errors(fra.me.REG[2]);
+      REGB1 = TAG_Int(3);
+      fra.me.REG[1] = NEW_Array_standard___collection___array___Array___with_capacity(REGB1);
+      if (!once_value_1) {
+        fra.me.REG[0] = BOX_NativeString("Parameter expected for option ");
+        REGB1 = TAG_Int(30);
+        fra.me.REG[0] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[0])(fra.me.REG[0], REGB1);
+        once_value_1 = fra.me.REG[0];
+        register_static_object(&once_value_1);
+      } else fra.me.REG[0] = once_value_1;
+      fra.me.REG[0] = fra.me.REG[0];
+      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[0]);
+      fra.me.REG[2] = CALL_opts___Option___names(fra.me.REG[2])(fra.me.REG[2]);
+      fra.me.REG[2] = CALL_standard___collection___abstract_collection___Collection___first(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]);
+      if (!once_value_2) {
+        fra.me.REG[2] = BOX_NativeString(".");
+        REGB1 = TAG_Int(1);
+        fra.me.REG[2] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[2])(fra.me.REG[2], REGB1);
+        once_value_2 = fra.me.REG[2];
+        register_static_object(&once_value_2);
+      } else fra.me.REG[2] = once_value_2;
+      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[1] = CALL_standard___string___Object___to_s(fra.me.REG[1])(fra.me.REG[1]);
+      CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
+    }
   }
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___OptionParameter___init_opt[] = "opts::OptionParameter::init_opt";
 void opts___OptionParameter___init_opt(val_t p0, val_t p1, val_t p2, val_t p3, int* init_table){
   int itpos4 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___OptionParameter].i;
-  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;
   if (init_table[itpos4]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 126;
+  fra.me.line = 151;
   fra.me.meth = LOCATE_opts___OptionParameter___init_opt;
   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;
   fra.me.REG[3] = p3;
-  /* ./../lib/opts.nit:126 */
+  /* ../lib/opts.nit:151 */
+  fra.me.REG[4] = fra.me.REG[0];
+  /* ../lib/opts.nit:153 */
   CALL_opts___Option___init_opt(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1], fra.me.REG[2], fra.me.REG[3], init_table);
+  /* ../lib/opts.nit:154 */
+  REGB0 = TAG_Bool(1);
+  ATTR_opts___OptionParameter____parameter_mandatory(fra.me.REG[4]) = REGB0;
   stack_frame_head = fra.me.prev;
   init_table[itpos4] = 1;
   return;
 }
+static const char LOCATE_opts___OptionString___init[] = "opts::OptionString::init";
 void opts___OptionString___init(val_t p0, val_t p1, val_t p2, int* init_table){
   int itpos5 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___OptionString].i;
   struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
@@ -732,7 +957,7 @@ void opts___OptionString___init(val_t p0, val_t p1, val_t p2, int* init_table){
   if (init_table[itpos5]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 133;
+  fra.me.line = 162;
   fra.me.meth = LOCATE_opts___OptionString___init;
   fra.me.has_broke = 0;
   fra.me.REG_size = 4;
@@ -744,24 +969,25 @@ void opts___OptionString___init(val_t p0, val_t p1, val_t p2, int* init_table){
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
   fra.me.REG[2] = p2;
-  /* ./../lib/opts.nit:133 */
+  /* ../lib/opts.nit:162 */
   fra.me.REG[3] = fra.me.REG[0];
   REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[2], COLOR_standard___collection___array___Array, ID_standard___collection___array___Array)) /*cast Array[String]*/;
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Cast failed", NULL, LOCATE_opts, 133);
+    nit_abort("Cast failed", NULL, LOCATE_opts, 162);
   }
   CALL_opts___OptionParameter___init_opt(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1], NIT_NULL, fra.me.REG[2], init_table);
   stack_frame_head = fra.me.prev;
   init_table[itpos5] = 1;
   return;
 }
+static const char LOCATE_opts___OptionString___convert[] = "opts::OptionString::(opts::OptionParameter::convert)";
 val_t opts___OptionString___convert(val_t p0, val_t p1){
   struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 135;
+  fra.me.line = 164;
   fra.me.meth = LOCATE_opts___OptionString___convert;
   fra.me.has_broke = 0;
   fra.me.REG_size = 2;
@@ -770,12 +996,13 @@ val_t opts___OptionString___convert(val_t p0, val_t p1){
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:135 */
+  /* ../lib/opts.nit:164 */
   goto label1;
   label1: while(0);
   stack_frame_head = fra.me.prev;
   return fra.me.REG[1];
 }
+static const char LOCATE_opts___OptionEnum___init[] = "opts::OptionEnum::init";
 void opts___OptionEnum___init(val_t p0, val_t p1, val_t p2, val_t p3, val_t p4, int* init_table){
   int itpos6 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___OptionEnum].i;
   struct {struct stack_frame_t me; val_t MORE_REG[5];} fra;
@@ -791,7 +1018,7 @@ void opts___OptionEnum___init(val_t p0, val_t p1, val_t p2, val_t p3, val_t p4,
   if (init_table[itpos6]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 143;
+  fra.me.line = 172;
   fra.me.meth = LOCATE_opts___OptionEnum___init;
   fra.me.has_broke = 0;
   fra.me.REG_size = 6;
@@ -807,44 +1034,44 @@ void opts___OptionEnum___init(val_t p0, val_t p1, val_t p2, val_t p3, val_t p4,
   fra.me.REG[2] = p2;
   REGB0 = p3;
   fra.me.REG[3] = p4;
-  /* ./../lib/opts.nit:143 */
+  /* ../lib/opts.nit:172 */
   fra.me.REG[4] = fra.me.REG[0];
   REGB1 = TAG_Bool(VAL_ISA(fra.me.REG[3], COLOR_standard___collection___array___Array, ID_standard___collection___array___Array)) /*cast Array[String]*/;
   if (UNTAG_Bool(REGB1)) {
   } else {
-    nit_abort("Cast failed", NULL, LOCATE_opts, 143);
+    nit_abort("Cast failed", NULL, LOCATE_opts, 172);
   }
-  /* ./../lib/standard//collection//array.nit:24 */
+  /* ../lib/standard/collection/array.nit:24 */
   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, 24);
   }
   REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1]);
-  /* ./../lib/opts.nit:145 */
+  /* ../lib/opts.nit:174 */
   REGB2 = TAG_Int(0);
   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 */
+  /* ../lib/standard/kernel.nit:244 */
   REGB2 = TAG_Bool(UNTAG_Int(REGB1)>UNTAG_Int(REGB2));
-  /* ./../lib/opts.nit:145 */
+  /* ../lib/opts.nit:174 */
   if (UNTAG_Bool(REGB2)) {
   } else {
-    nit_abort("Assert failed", NULL, LOCATE_opts, 145);
+    nit_abort("Assert failed", NULL, LOCATE_opts, 174);
   }
-  /* ./../lib/opts.nit:146 */
+  /* ../lib/opts.nit:175 */
   fra.me.REG[0] = CALL_standard___collection___array___Collection___to_a(fra.me.REG[1])(fra.me.REG[1]);
   ATTR_opts___OptionEnum____values(fra.me.REG[4]) = fra.me.REG[0];
-  /* ./../lib/opts.nit:147 */
+  /* ../lib/opts.nit:176 */
   REGB2 = TAG_Int(5);
   fra.me.REG[0] = NEW_Array_standard___collection___array___Array___with_capacity(REGB2);
   if (!once_value_1) {
     fra.me.REG[5] = BOX_NativeString("");
     REGB2 = TAG_Int(0);
-    fra.me.REG[5] = NEW_String_standard___string___String___with_native(fra.me.REG[5], REGB2);
+    fra.me.REG[5] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[5])(fra.me.REG[5], REGB2);
     once_value_1 = fra.me.REG[5];
     register_static_object(&once_value_1);
   } else fra.me.REG[5] = once_value_1;
@@ -854,7 +1081,7 @@ void opts___OptionEnum___init(val_t p0, val_t p1, val_t p2, val_t p3, val_t p4,
   if (!once_value_2) {
     fra.me.REG[2] = BOX_NativeString(" <");
     REGB2 = TAG_Int(2);
-    fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB2);
+    fra.me.REG[2] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[2])(fra.me.REG[2], REGB2);
     once_value_2 = fra.me.REG[2];
     register_static_object(&once_value_2);
   } else fra.me.REG[2] = once_value_2;
@@ -863,7 +1090,7 @@ void opts___OptionEnum___init(val_t p0, val_t p1, val_t p2, val_t p3, val_t p4,
   if (!once_value_3) {
     fra.me.REG[2] = BOX_NativeString(", ");
     REGB2 = TAG_Int(2);
-    fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB2);
+    fra.me.REG[2] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[2])(fra.me.REG[2], REGB2);
     once_value_3 = fra.me.REG[2];
     register_static_object(&once_value_3);
   } else fra.me.REG[2] = once_value_3;
@@ -873,7 +1100,7 @@ void opts___OptionEnum___init(val_t p0, val_t p1, val_t p2, val_t p3, val_t p4,
   if (!once_value_4) {
     fra.me.REG[2] = BOX_NativeString(">");
     REGB2 = TAG_Int(1);
-    fra.me.REG[2] = NEW_String_standard___string___String___with_native(fra.me.REG[2], REGB2);
+    fra.me.REG[2] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[2])(fra.me.REG[2], REGB2);
     once_value_4 = fra.me.REG[2];
     register_static_object(&once_value_4);
   } else fra.me.REG[2] = once_value_4;
@@ -885,35 +1112,149 @@ void opts___OptionEnum___init(val_t p0, val_t p1, val_t p2, val_t p3, val_t p4,
   init_table[itpos6] = 1;
   return;
 }
+static const char LOCATE_opts___OptionEnum___convert[] = "opts::OptionEnum::(opts::OptionParameter::convert)";
 val_t opts___OptionEnum___convert(val_t p0, val_t p1){
-  struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[4];} fra;
   val_t REGB0;
+  val_t REGB1;
+  val_t REGB2;
   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_opts;
-  fra.me.line = 150;
+  fra.me.line = 179;
   fra.me.meth = LOCATE_opts___OptionEnum___convert;
   fra.me.has_broke = 0;
-  fra.me.REG_size = 2;
+  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;
-  /* ./../lib/opts.nit:152 */
+  /* ../lib/opts.nit:181 */
   REGB0 = TAG_Bool(ATTR_opts___OptionEnum____values(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 152);
+    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 181);
   }
-  fra.me.REG[0] = ATTR_opts___OptionEnum____values(fra.me.REG[0]);
-  REGB0 = CALL_standard___collection___abstract_collection___SequenceRead___index_of(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
-  /* ./../lib/opts.nit:153 */
-  goto label1;
-  label1: while(0);
+  fra.me.REG[2] = ATTR_opts___OptionEnum____values(fra.me.REG[0]);
+  REGB0 = CALL_standard___collection___abstract_collection___SequenceRead___index_of(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
+  /* ../lib/opts.nit:182 */
+  REGB1 = TAG_Int(1);
+  /* ../lib/standard/kernel.nit:246 */
+  REGB1 = TAG_Int(-UNTAG_Int(REGB1));
+  /* ../lib/opts.nit:182 */
+  REGB2 = TAG_Bool(IS_EQUAL_OO(REGB0,REGB1));
+  if (UNTAG_Bool(REGB2)) {
+  } else {
+    /* ../lib/standard/kernel.nit:237 */
+    REGB1 = TAG_Bool((REGB0)==(REGB1));
+    /* ../lib/opts.nit:182 */
+    REGB2 = REGB1;
+  }
+  if (UNTAG_Bool(REGB2)) {
+    /* ../lib/opts.nit:183 */
+    REGB2 = TAG_Int(3);
+    fra.me.REG[1] = NEW_Array_standard___collection___array___Array___with_capacity(REGB2);
+    if (!once_value_1) {
+      fra.me.REG[2] = BOX_NativeString("Unrecognized value for option ");
+      REGB2 = TAG_Int(30);
+      fra.me.REG[2] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[2])(fra.me.REG[2], REGB2);
+      once_value_1 = fra.me.REG[2];
+      register_static_object(&once_value_1);
+    } else fra.me.REG[2] = once_value_1;
+    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]);
+    REGB2 = TAG_Bool(ATTR_opts___Option____names(fra.me.REG[0])!=NIT_NULL);
+    if (UNTAG_Bool(REGB2)) {
+    } else {
+      nit_abort("Uninitialized attribute %s", "_names", LOCATE_opts, 183);
+    }
+    fra.me.REG[2] = ATTR_opts___Option____names(fra.me.REG[0]);
+    if (!once_value_2) {
+      fra.me.REG[3] = BOX_NativeString(", ");
+      REGB2 = TAG_Int(2);
+      fra.me.REG[3] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[3])(fra.me.REG[3], REGB2);
+      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];
+    fra.me.REG[3] = CALL_standard___string___Collection___join(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_3) {
+      fra.me.REG[3] = BOX_NativeString(".\n");
+      REGB2 = TAG_Int(2);
+      fra.me.REG[3] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[3])(fra.me.REG[3], REGB2);
+      once_value_3 = fra.me.REG[3];
+      register_static_object(&once_value_3);
+    } 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[1] = CALL_standard___string___Object___to_s(fra.me.REG[1])(fra.me.REG[1]);
+    /* ../lib/opts.nit:184 */
+    REGB2 = TAG_Int(3);
+    fra.me.REG[3] = NEW_Array_standard___collection___array___Array___with_capacity(REGB2);
+    if (!once_value_4) {
+      fra.me.REG[2] = BOX_NativeString("Expected values are: ");
+      REGB2 = TAG_Int(21);
+      fra.me.REG[2] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[2])(fra.me.REG[2], REGB2);
+      once_value_4 = fra.me.REG[2];
+      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[3])(fra.me.REG[3], fra.me.REG[2]);
+    REGB2 = TAG_Bool(ATTR_opts___OptionEnum____values(fra.me.REG[0])!=NIT_NULL);
+    if (UNTAG_Bool(REGB2)) {
+    } else {
+      nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 184);
+    }
+    fra.me.REG[2] = ATTR_opts___OptionEnum____values(fra.me.REG[0]);
+    if (!once_value_5) {
+      fra.me.REG[4] = BOX_NativeString(", ");
+      REGB2 = TAG_Int(2);
+      fra.me.REG[4] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[4])(fra.me.REG[4], REGB2);
+      once_value_5 = fra.me.REG[4];
+      register_static_object(&once_value_5);
+    } else fra.me.REG[4] = once_value_5;
+    fra.me.REG[4] = fra.me.REG[4];
+    fra.me.REG[4] = CALL_standard___string___Collection___join(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_6) {
+      fra.me.REG[4] = BOX_NativeString(".");
+      REGB2 = TAG_Int(1);
+      fra.me.REG[4] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[4])(fra.me.REG[4], REGB2);
+      once_value_6 = fra.me.REG[4];
+      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]);
+    fra.me.REG[3] = CALL_standard___string___Object___to_s(fra.me.REG[3])(fra.me.REG[3]);
+    fra.me.REG[3] = CALL_standard___string___String_____plus(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[3]);
+    fra.me.REG[1] = fra.me.REG[3];
+    /* ../lib/opts.nit:185 */
+    REGB2 = TAG_Bool(ATTR_opts___Option____errors(fra.me.REG[0])!=NIT_NULL);
+    if (UNTAG_Bool(REGB2)) {
+    } else {
+      nit_abort("Uninitialized attribute %s", "_errors", LOCATE_opts, 185);
+    }
+    fra.me.REG[0] = ATTR_opts___Option____errors(fra.me.REG[0]);
+    CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
+  }
+  /* ../lib/opts.nit:187 */
+  goto label7;
+  label7: while(0);
   stack_frame_head = fra.me.prev;
   return REGB0;
 }
+static const char LOCATE_opts___OptionEnum___value_name[] = "opts::OptionEnum::value_name";
 val_t opts___OptionEnum___value_name(val_t p0){
   struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
   val_t REGB0;
@@ -922,7 +1263,7 @@ val_t opts___OptionEnum___value_name(val_t p0){
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 156;
+  fra.me.line = 190;
   fra.me.meth = LOCATE_opts___OptionEnum___value_name;
   fra.me.has_broke = 0;
   fra.me.REG_size = 2;
@@ -930,31 +1271,31 @@ val_t opts___OptionEnum___value_name(val_t p0){
   fra.me.REG[0] = NIT_NULL;
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[0] = p0;
-  /* ./../lib/opts.nit:156 */
+  /* ../lib/opts.nit:190 */
   REGB0 = TAG_Bool(ATTR_opts___OptionEnum____values(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 156);
+    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 190);
   }
   fra.me.REG[1] = ATTR_opts___OptionEnum____values(fra.me.REG[0]);
   fra.me.REG[0] = CALL_opts___Option___value(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./../lib/standard//collection//array.nit:278 */
+  /* ../lib/standard/collection/array.nit:279 */
   REGB0 = fra.me.REG[0];
-  /* ./../lib/standard//collection//array.nit:280 */
+  /* ../lib/standard/collection/array.nit:281 */
   REGB1 = TAG_Int(0);
   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 */
+  /* ../lib/standard/kernel.nit:243 */
   REGB1 = TAG_Bool(UNTAG_Int(REGB0)>=UNTAG_Int(REGB1));
-  /* ./../lib/standard//collection//array.nit:280 */
+  /* ../lib/standard/collection/array.nit:281 */
   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, 280);
+      nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 281);
     }
     REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1]);
     REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
@@ -962,34 +1303,35 @@ val_t opts___OptionEnum___value_name(val_t p0){
     } else {
       nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
     }
-    /* ./../lib/standard//kernel.nit:232 */
+    /* ../lib/standard/kernel.nit:242 */
     REGB1 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
   } else {
-    /* ./../lib/standard//collection//array.nit:280 */
-    REGB2 = TAG_Bool(false);
+    /* ../lib/standard/collection/array.nit:281 */
+    REGB2 = TAG_Bool(0);
     REGB1 = REGB2;
   }
   if (UNTAG_Bool(REGB1)) {
   } else {
-    nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 280);
+    nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 281);
   }
-  /* ./../lib/standard//collection//array.nit:281 */
+  /* ../lib/standard/collection/array.nit:282 */
   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, 281);
+    nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 282);
   }
-  /* ./../lib/standard//collection//array.nit:718 */
+  /* ../lib/standard/collection/array.nit:725 */
   fra.me.REG[1] = ((Nit_NativeArray)fra.me.REG[1])->val[UNTAG_Int(REGB0)];
-  /* ./../lib/standard//collection//array.nit:281 */
+  /* ../lib/standard/collection/array.nit:282 */
   goto label1;
   label1: while(0);
-  /* ./../lib/opts.nit:156 */
+  /* ../lib/opts.nit:190 */
   goto label2;
   label2: while(0);
   stack_frame_head = fra.me.prev;
   return fra.me.REG[1];
 }
+static const char LOCATE_opts___OptionEnum___pretty_default[] = "opts::OptionEnum::(opts::Option::pretty_default)";
 val_t opts___OptionEnum___pretty_default(val_t p0){
   struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
   val_t REGB0;
@@ -1001,7 +1343,7 @@ val_t opts___OptionEnum___pretty_default(val_t p0){
     static val_t once_value_5; /* Once value */
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 158;
+  fra.me.line = 192;
   fra.me.meth = LOCATE_opts___OptionEnum___pretty_default;
   fra.me.has_broke = 0;
   fra.me.REG_size = 4;
@@ -1011,33 +1353,33 @@ val_t opts___OptionEnum___pretty_default(val_t p0){
   fra.me.REG[2] = NIT_NULL;
   fra.me.REG[3] = NIT_NULL;
   fra.me.REG[0] = p0;
-  /* ./../lib/opts.nit:158 */
+  /* ../lib/opts.nit:192 */
   fra.me.REG[1] = fra.me.REG[0];
-  /* ./../lib/opts.nit:160 */
+  /* ../lib/opts.nit:194 */
   fra.me.REG[2] = CALL_opts___Option___default_value(fra.me.REG[1])(fra.me.REG[1]);
   REGB0 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
     REGB1 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
     if (UNTAG_Bool(REGB1)) {
-      REGB1 = TAG_Bool(false);
+      REGB1 = TAG_Bool(0);
       REGB0 = REGB1;
     } else {
-      /* ./../lib/standard//kernel.nit:227 */
+      /* ../lib/standard/kernel.nit:237 */
       REGB1 = TAG_Bool((fra.me.REG[2])==(NIT_NULL));
-      /* ./../lib/opts.nit:160 */
+      /* ../lib/opts.nit:194 */
       REGB0 = REGB1;
     }
   }
   REGB0 = TAG_Bool(!UNTAG_Bool(REGB0));
   if (UNTAG_Bool(REGB0)) {
-    /* ./../lib/opts.nit:161 */
+    /* ../lib/opts.nit:195 */
     REGB0 = TAG_Int(3);
     fra.me.REG[2] = NEW_Array_standard___collection___array___Array___with_capacity(REGB0);
     if (!once_value_1) {
       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);
+      fra.me.REG[3] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[3])(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;
@@ -1046,32 +1388,32 @@ val_t opts___OptionEnum___pretty_default(val_t p0){
     REGB0 = TAG_Bool(ATTR_opts___OptionEnum____values(fra.me.REG[1])!=NIT_NULL);
     if (UNTAG_Bool(REGB0)) {
     } else {
-      nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 161);
+      nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 195);
     }
     fra.me.REG[3] = ATTR_opts___OptionEnum____values(fra.me.REG[1]);
     fra.me.REG[1] = CALL_opts___Option___default_value(fra.me.REG[1])(fra.me.REG[1]);
     REGB0 = TAG_Bool((fra.me.REG[1]!=NIT_NULL) && VAL_ISA(fra.me.REG[1], VTCOLOR_opts___Option___VALUE(fra.me.REG[0]), VTID_opts___Option___VALUE(fra.me.REG[0]))) /*cast VALUE*/;
     if (UNTAG_Bool(REGB0)) {
     } else {
-      nit_abort("Cast failed", NULL, LOCATE_opts, 161);
+      nit_abort("Cast failed", NULL, LOCATE_opts, 195);
     }
-    /* ./../lib/standard//collection//array.nit:278 */
+    /* ../lib/standard/collection/array.nit:279 */
     REGB0 = fra.me.REG[1];
-    /* ./../lib/standard//collection//array.nit:280 */
+    /* ../lib/standard/collection/array.nit:281 */
     REGB1 = TAG_Int(0);
     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 */
+    /* ../lib/standard/kernel.nit:243 */
     REGB1 = TAG_Bool(UNTAG_Int(REGB0)>=UNTAG_Int(REGB1));
-    /* ./../lib/standard//collection//array.nit:280 */
+    /* ../lib/standard/collection/array.nit:281 */
     if (UNTAG_Bool(REGB1)) {
       REGB1 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3])!=NIT_NULL);
       if (UNTAG_Bool(REGB1)) {
       } else {
-        nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 280);
+        nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 281);
       }
       REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3]);
       REGB2 = TAG_Bool(VAL_ISA(REGB1, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
@@ -1079,34 +1421,34 @@ val_t opts___OptionEnum___pretty_default(val_t p0){
       } else {
         nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
       }
-      /* ./../lib/standard//kernel.nit:232 */
+      /* ../lib/standard/kernel.nit:242 */
       REGB1 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
     } else {
-      /* ./../lib/standard//collection//array.nit:280 */
-      REGB2 = TAG_Bool(false);
+      /* ../lib/standard/collection/array.nit:281 */
+      REGB2 = TAG_Bool(0);
       REGB1 = REGB2;
     }
     if (UNTAG_Bool(REGB1)) {
     } else {
-      nit_abort("Assert %s  failed", "'index'", LOCATE_standard___collection___array, 280);
+      nit_abort("Assert '%s' failed", "index", LOCATE_standard___collection___array, 281);
     }
-    /* ./../lib/standard//collection//array.nit:281 */
+    /* ../lib/standard/collection/array.nit:282 */
     fra.me.REG[3] = ATTR_standard___collection___array___Array____items(fra.me.REG[3]);
     REGB1 = TAG_Bool(fra.me.REG[3]==NIT_NULL);
     if (UNTAG_Bool(REGB1)) {
-      nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 281);
+      nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 282);
     }
-    /* ./../lib/standard//collection//array.nit:718 */
+    /* ../lib/standard/collection/array.nit:725 */
     fra.me.REG[3] = ((Nit_NativeArray)fra.me.REG[3])->val[UNTAG_Int(REGB0)];
-    /* ./../lib/standard//collection//array.nit:281 */
+    /* ../lib/standard/collection/array.nit:282 */
     goto label2;
     label2: while(0);
-    /* ./../lib/opts.nit:161 */
+    /* ../lib/opts.nit:195 */
     CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[3]);
     if (!once_value_3) {
       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);
+      fra.me.REG[3] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[3])(fra.me.REG[3], REGB0);
       once_value_3 = fra.me.REG[3];
       register_static_object(&once_value_3);
     } else fra.me.REG[3] = once_value_3;
@@ -1115,11 +1457,11 @@ val_t opts___OptionEnum___pretty_default(val_t p0){
     fra.me.REG[2] = CALL_standard___string___Object___to_s(fra.me.REG[2])(fra.me.REG[2]);
     goto label4;
   } else {
-    /* ./../lib/opts.nit:163 */
+    /* ../lib/opts.nit:197 */
     if (!once_value_5) {
       fra.me.REG[3] = BOX_NativeString("");
       REGB0 = TAG_Int(0);
-      fra.me.REG[3] = NEW_String_standard___string___String___with_native(fra.me.REG[3], REGB0);
+      fra.me.REG[3] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[3])(fra.me.REG[3], REGB0);
       once_value_5 = fra.me.REG[3];
       register_static_object(&once_value_5);
     } else fra.me.REG[3] = once_value_5;
@@ -1131,6 +1473,7 @@ val_t opts___OptionEnum___pretty_default(val_t p0){
   stack_frame_head = fra.me.prev;
   return fra.me.REG[2];
 }
+static const char LOCATE_opts___OptionInt___init[] = "opts::OptionInt::init";
 void opts___OptionInt___init(val_t p0, val_t p1, val_t p2, val_t p3, int* init_table){
   int itpos7 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___OptionInt].i;
   struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
@@ -1140,7 +1483,7 @@ void opts___OptionInt___init(val_t p0, val_t p1, val_t p2, val_t p3, int* init_t
   if (init_table[itpos7]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 172;
+  fra.me.line = 206;
   fra.me.meth = LOCATE_opts___OptionInt___init;
   fra.me.has_broke = 0;
   fra.me.REG_size = 4;
@@ -1153,25 +1496,26 @@ void opts___OptionInt___init(val_t p0, val_t p1, val_t p2, val_t p3, int* init_t
   fra.me.REG[1] = p1;
   REGB0 = p2;
   fra.me.REG[2] = p3;
-  /* ./../lib/opts.nit:172 */
+  /* ../lib/opts.nit:206 */
   fra.me.REG[3] = fra.me.REG[0];
   REGB1 = TAG_Bool(VAL_ISA(fra.me.REG[2], COLOR_standard___collection___array___Array, ID_standard___collection___array___Array)) /*cast Array[String]*/;
   if (UNTAG_Bool(REGB1)) {
   } else {
-    nit_abort("Cast failed", NULL, LOCATE_opts, 172);
+    nit_abort("Cast failed", NULL, LOCATE_opts, 206);
   }
   CALL_opts___OptionParameter___init_opt(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1], REGB0, fra.me.REG[2], init_table);
   stack_frame_head = fra.me.prev;
   init_table[itpos7] = 1;
   return;
 }
+static const char LOCATE_opts___OptionInt___convert[] = "opts::OptionInt::(opts::OptionParameter::convert)";
 val_t opts___OptionInt___convert(val_t p0, val_t p1){
   struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 174;
+  fra.me.line = 208;
   fra.me.meth = LOCATE_opts___OptionInt___convert;
   fra.me.has_broke = 0;
   fra.me.REG_size = 2;
@@ -1180,13 +1524,14 @@ val_t opts___OptionInt___convert(val_t p0, val_t p1){
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:174 */
+  /* ../lib/opts.nit:208 */
   REGB0 = CALL_standard___string___AbstractString___to_i(fra.me.REG[1])(fra.me.REG[1]);
   goto label1;
   label1: while(0);
   stack_frame_head = fra.me.prev;
   return REGB0;
 }
+static const char LOCATE_opts___OptionArray___init[] = "opts::OptionArray::init";
 void opts___OptionArray___init(val_t p0, val_t p1, val_t p2, int* init_table){
   int itpos8 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___OptionArray].i;
   struct {struct stack_frame_t me; val_t MORE_REG[3];} fra;
@@ -1195,7 +1540,7 @@ void opts___OptionArray___init(val_t p0, val_t p1, val_t p2, int* init_table){
   if (init_table[itpos8]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 181;
+  fra.me.line = 215;
   fra.me.meth = LOCATE_opts___OptionArray___init;
   fra.me.has_broke = 0;
   fra.me.REG_size = 4;
@@ -1207,21 +1552,21 @@ void opts___OptionArray___init(val_t p0, val_t p1, val_t p2, int* init_table){
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
   fra.me.REG[2] = p2;
-  /* ./../lib/opts.nit:181 */
+  /* ../lib/opts.nit:215 */
   fra.me.REG[3] = fra.me.REG[0];
   REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[2], COLOR_standard___collection___array___Array, ID_standard___collection___array___Array)) /*cast Array[String]*/;
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Cast failed", NULL, LOCATE_opts, 181);
+    nit_abort("Cast failed", NULL, LOCATE_opts, 215);
   }
-  /* ./../lib/opts.nit:183 */
+  /* ../lib/opts.nit:217 */
   fra.me.REG[0] = NEW_Array_standard___collection___array___Array___init();
   ATTR_opts___OptionArray____values(fra.me.REG[3]) = fra.me.REG[0];
-  /* ./../lib/opts.nit:184 */
+  /* ../lib/opts.nit:218 */
   REGB0 = TAG_Bool(ATTR_opts___OptionArray____values(fra.me.REG[3])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 184);
+    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 218);
   }
   fra.me.REG[0] = ATTR_opts___OptionArray____values(fra.me.REG[3]);
   CALL_opts___OptionParameter___init_opt(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1], fra.me.REG[0], fra.me.REG[2], init_table);
@@ -1229,13 +1574,14 @@ void opts___OptionArray___init(val_t p0, val_t p1, val_t p2, int* init_table){
   init_table[itpos8] = 1;
   return;
 }
+static const char LOCATE_opts___OptionArray___convert[] = "opts::OptionArray::(opts::OptionParameter::convert)";
 val_t opts___OptionArray___convert(val_t p0, val_t p1){
   struct {struct stack_frame_t me; val_t MORE_REG[2];} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 188;
+  fra.me.line = 222;
   fra.me.meth = LOCATE_opts___OptionArray___convert;
   fra.me.has_broke = 0;
   fra.me.REG_size = 3;
@@ -1245,19 +1591,19 @@ val_t opts___OptionArray___convert(val_t p0, val_t p1){
   fra.me.REG[2] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:190 */
+  /* ../lib/opts.nit:224 */
   REGB0 = TAG_Bool(ATTR_opts___OptionArray____values(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 190);
+    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 224);
   }
   fra.me.REG[2] = ATTR_opts___OptionArray____values(fra.me.REG[0]);
   CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[1]);
-  /* ./../lib/opts.nit:191 */
+  /* ../lib/opts.nit:225 */
   REGB0 = TAG_Bool(ATTR_opts___OptionArray____values(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 191);
+    nit_abort("Uninitialized attribute %s", "_values", LOCATE_opts, 225);
   }
   fra.me.REG[0] = ATTR_opts___OptionArray____values(fra.me.REG[0]);
   goto label1;
@@ -1265,52 +1611,79 @@ val_t opts___OptionArray___convert(val_t p0, val_t p1){
   stack_frame_head = fra.me.prev;
   return fra.me.REG[0];
 }
+static const char LOCATE_opts___OptionContext___options[] = "opts::OptionContext::options";
 val_t opts___OptionContext___options(val_t p0){
   struct {struct stack_frame_t me;} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 196;
+  fra.me.line = 230;
   fra.me.meth = LOCATE_opts___OptionContext___options;
   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;
-  /* ./../lib/opts.nit:196 */
+  /* ../lib/opts.nit:230 */
   REGB0 = TAG_Bool(ATTR_opts___OptionContext____options(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 196);
+    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 230);
   }
   fra.me.REG[0] = ATTR_opts___OptionContext____options(fra.me.REG[0]);
   stack_frame_head = fra.me.prev;
   return fra.me.REG[0];
 }
+static const char LOCATE_opts___OptionContext___rest[] = "opts::OptionContext::rest";
 val_t opts___OptionContext___rest(val_t p0){
   struct {struct stack_frame_t me;} fra;
   val_t REGB0;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 197;
+  fra.me.line = 231;
   fra.me.meth = LOCATE_opts___OptionContext___rest;
   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;
-  /* ./../lib/opts.nit:197 */
+  /* ../lib/opts.nit:231 */
   REGB0 = TAG_Bool(ATTR_opts___OptionContext____rest(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_rest", LOCATE_opts, 197);
+    nit_abort("Uninitialized attribute %s", "_rest", LOCATE_opts, 231);
   }
   fra.me.REG[0] = ATTR_opts___OptionContext____rest(fra.me.REG[0]);
   stack_frame_head = fra.me.prev;
   return fra.me.REG[0];
 }
+static const char LOCATE_opts___OptionContext___errors[] = "opts::OptionContext::errors";
+val_t opts___OptionContext___errors(val_t p0){
+  struct {struct stack_frame_t me;} fra;
+  val_t REGB0;
+  val_t tmp;
+  fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
+  fra.me.file = LOCATE_opts;
+  fra.me.line = 232;
+  fra.me.meth = LOCATE_opts___OptionContext___errors;
+  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;
+  /* ../lib/opts.nit:232 */
+  REGB0 = TAG_Bool(ATTR_opts___OptionContext____errors(fra.me.REG[0])!=NIT_NULL);
+  if (UNTAG_Bool(REGB0)) {
+  } else {
+    nit_abort("Uninitialized attribute %s", "_errors", LOCATE_opts, 232);
+  }
+  fra.me.REG[0] = ATTR_opts___OptionContext____errors(fra.me.REG[0]);
+  stack_frame_head = fra.me.prev;
+  return fra.me.REG[0];
+}
+static const char LOCATE_opts___OptionContext___usage[] = "opts::OptionContext::usage";
 void opts___OptionContext___usage(val_t p0){
   struct {struct stack_frame_t me; val_t MORE_REG[5];} fra;
   val_t REGB0;
@@ -1322,7 +1695,7 @@ void opts___OptionContext___usage(val_t p0){
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 201;
+  fra.me.line = 236;
   fra.me.meth = LOCATE_opts___OptionContext___usage;
   fra.me.has_broke = 0;
   fra.me.REG_size = 6;
@@ -1334,29 +1707,29 @@ void opts___OptionContext___usage(val_t p0){
   fra.me.REG[4] = NIT_NULL;
   fra.me.REG[5] = NIT_NULL;
   fra.me.REG[0] = p0;
-  /* ./../lib/opts.nit:203 */
+  /* ../lib/opts.nit:238 */
   REGB0 = TAG_Int(1);
-  /* ./../lib/opts.nit:204 */
+  /* ../lib/opts.nit:239 */
   REGB1 = TAG_Bool(ATTR_opts___OptionContext____options(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB1)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 204);
+    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 239);
   }
   fra.me.REG[1] = ATTR_opts___OptionContext____options(fra.me.REG[0]);
-  /* ./../lib/standard//collection//array.nit:269 */
+  /* ../lib/standard/collection/array.nit:270 */
   REGB1 = TAG_Int(0);
-  /* ./../lib/standard//collection//array.nit:270 */
+  /* ../lib/standard/collection/array.nit:271 */
   REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1])!=NIT_NULL);
   if (UNTAG_Bool(REGB2)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 270);
+    nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 271);
   }
   REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1]);
-  /* ./../lib/standard//collection//array.nit:271 */
+  /* ../lib/standard/collection/array.nit:272 */
   fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[1]);
-  /* ./../lib/standard//collection//array.nit:272 */
+  /* ../lib/standard/collection/array.nit:273 */
   while(1) {
-    /* ./../lib/standard//collection//array.nit:24 */
+    /* ../lib/standard/collection/array.nit:24 */
     REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1])!=NIT_NULL);
     if (UNTAG_Bool(REGB2)) {
     } else {
@@ -1368,35 +1741,35 @@ void opts___OptionContext___usage(val_t p0){
     } else {
       nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
     }
-    /* ./../lib/standard//kernel.nit:232 */
+    /* ../lib/standard/kernel.nit:242 */
     REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
-    /* ./../lib/standard//collection//array.nit:272 */
+    /* ../lib/standard/collection/array.nit:273 */
     if (UNTAG_Bool(REGB2)) {
-      /* ./../lib/standard//collection//array.nit:273 */
+      /* ../lib/standard/collection/array.nit:274 */
       REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
       if (UNTAG_Bool(REGB2)) {
-        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 273);
+        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 274);
       }
-      /* ./../lib/standard//collection//array.nit:718 */
+      /* ../lib/standard/collection/array.nit:725 */
       fra.me.REG[3] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB1)];
-      /* ./../lib/opts.nit:205 */
+      /* ../lib/opts.nit:240 */
       REGB2 = TAG_Int(3);
-      /* ./../lib/opts.nit:206 */
+      /* ../lib/opts.nit:241 */
       fra.me.REG[3] = CALL_opts___Option___names(fra.me.REG[3])(fra.me.REG[3]);
-      /* ./../lib/standard//collection//array.nit:269 */
+      /* ../lib/standard/collection/array.nit:270 */
       REGB3 = TAG_Int(0);
-      /* ./../lib/standard//collection//array.nit:270 */
+      /* ../lib/standard/collection/array.nit:271 */
       REGB4 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3])!=NIT_NULL);
       if (UNTAG_Bool(REGB4)) {
       } else {
-        nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 270);
+        nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 271);
       }
       REGB4 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3]);
-      /* ./../lib/standard//collection//array.nit:271 */
+      /* ../lib/standard/collection/array.nit:272 */
       fra.me.REG[4] = ATTR_standard___collection___array___Array____items(fra.me.REG[3]);
-      /* ./../lib/standard//collection//array.nit:272 */
+      /* ../lib/standard/collection/array.nit:273 */
       while(1) {
-        /* ./../lib/standard//collection//array.nit:24 */
+        /* ../lib/standard/collection/array.nit:24 */
         REGB4 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3])!=NIT_NULL);
         if (UNTAG_Bool(REGB4)) {
         } else {
@@ -1408,39 +1781,39 @@ void opts___OptionContext___usage(val_t p0){
         } else {
           nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
         }
-        /* ./../lib/standard//kernel.nit:232 */
+        /* ../lib/standard/kernel.nit:242 */
         REGB4 = TAG_Bool(UNTAG_Int(REGB3)<UNTAG_Int(REGB4));
-        /* ./../lib/standard//collection//array.nit:272 */
+        /* ../lib/standard/collection/array.nit:273 */
         if (UNTAG_Bool(REGB4)) {
-          /* ./../lib/standard//collection//array.nit:273 */
+          /* ../lib/standard/collection/array.nit:274 */
           REGB4 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
           if (UNTAG_Bool(REGB4)) {
-            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 273);
+            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 274);
           }
-          /* ./../lib/standard//collection//array.nit:718 */
+          /* ../lib/standard/collection/array.nit:725 */
           fra.me.REG[5] = ((Nit_NativeArray)fra.me.REG[4])->val[UNTAG_Int(REGB3)];
-          /* ./../lib/standard//collection//array.nit:24 */
+          /* ../lib/standard/collection/array.nit:24 */
           REGB4 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[5])!=NIT_NULL);
           if (UNTAG_Bool(REGB4)) {
           } else {
             nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 24);
           }
           REGB4 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[5]);
-          /* ./../lib/opts.nit:207 */
+          /* ../lib/opts.nit:242 */
           REGB5 = TAG_Int(2);
-          /* ./../lib/standard//kernel.nit:235 */
+          /* ../lib/standard/kernel.nit:245 */
           REGB5 = TAG_Int(UNTAG_Int(REGB4)+UNTAG_Int(REGB5));
           REGB5 = TAG_Int(UNTAG_Int(REGB2)+UNTAG_Int(REGB5));
-          /* ./../lib/opts.nit:207 */
+          /* ../lib/opts.nit:242 */
           REGB2 = REGB5;
-          /* ./../lib/standard//collection//array.nit:274 */
+          /* ../lib/standard/collection/array.nit:275 */
           REGB5 = TAG_Int(1);
-          /* ./../lib/standard//kernel.nit:235 */
+          /* ../lib/standard/kernel.nit:245 */
           REGB5 = TAG_Int(UNTAG_Int(REGB3)+UNTAG_Int(REGB5));
-          /* ./../lib/standard//collection//array.nit:274 */
+          /* ../lib/standard/collection/array.nit:275 */
           REGB3 = REGB5;
         } else {
-          /* ./../lib/standard//collection//array.nit:272 */
+          /* ../lib/standard/collection/array.nit:273 */
           goto label1;
         }
       }
@@ -1450,45 +1823,45 @@ void opts___OptionContext___usage(val_t p0){
       } else {
         nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
       }
-      /* ./../lib/standard//kernel.nit:232 */
+      /* ../lib/standard/kernel.nit:242 */
       REGB3 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB2));
-      /* ./../lib/opts.nit:209 */
+      /* ../lib/opts.nit:244 */
       if (UNTAG_Bool(REGB3)) {
         REGB0 = REGB2;
       }
-      /* ./../lib/standard//collection//array.nit:274 */
+      /* ../lib/standard/collection/array.nit:275 */
       REGB2 = TAG_Int(1);
-      /* ./../lib/standard//kernel.nit:235 */
+      /* ../lib/standard/kernel.nit:245 */
       REGB2 = TAG_Int(UNTAG_Int(REGB1)+UNTAG_Int(REGB2));
-      /* ./../lib/standard//collection//array.nit:274 */
+      /* ../lib/standard/collection/array.nit:275 */
       REGB1 = REGB2;
     } else {
-      /* ./../lib/standard//collection//array.nit:272 */
+      /* ../lib/standard/collection/array.nit:273 */
       goto label2;
     }
   }
   label2: while(0);
-  /* ./../lib/opts.nit:212 */
+  /* ../lib/opts.nit:247 */
   REGB1 = TAG_Bool(ATTR_opts___OptionContext____options(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB1)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 212);
+    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 247);
   }
   fra.me.REG[2] = ATTR_opts___OptionContext____options(fra.me.REG[0]);
-  /* ./../lib/standard//collection//array.nit:269 */
+  /* ../lib/standard/collection/array.nit:270 */
   REGB1 = TAG_Int(0);
-  /* ./../lib/standard//collection//array.nit:270 */
+  /* ../lib/standard/collection/array.nit:271 */
   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, 270);
+    nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 271);
   }
   REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2]);
-  /* ./../lib/standard//collection//array.nit:271 */
+  /* ../lib/standard/collection/array.nit:272 */
   fra.me.REG[1] = ATTR_standard___collection___array___Array____items(fra.me.REG[2]);
-  /* ./../lib/standard//collection//array.nit:272 */
+  /* ../lib/standard/collection/array.nit:273 */
   while(1) {
-    /* ./../lib/standard//collection//array.nit:24 */
+    /* ../lib/standard/collection/array.nit:24 */
     REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[2])!=NIT_NULL);
     if (UNTAG_Bool(REGB2)) {
     } else {
@@ -1500,28 +1873,28 @@ void opts___OptionContext___usage(val_t p0){
     } else {
       nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
     }
-    /* ./../lib/standard//kernel.nit:232 */
+    /* ../lib/standard/kernel.nit:242 */
     REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
-    /* ./../lib/standard//collection//array.nit:272 */
+    /* ../lib/standard/collection/array.nit:273 */
     if (UNTAG_Bool(REGB2)) {
-      /* ./../lib/standard//collection//array.nit:273 */
+      /* ../lib/standard/collection/array.nit:274 */
       REGB2 = TAG_Bool(fra.me.REG[1]==NIT_NULL);
       if (UNTAG_Bool(REGB2)) {
-        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 273);
+        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 274);
       }
-      /* ./../lib/standard//collection//array.nit:718 */
+      /* ../lib/standard/collection/array.nit:725 */
       fra.me.REG[4] = ((Nit_NativeArray)fra.me.REG[1])->val[UNTAG_Int(REGB1)];
-      /* ./../lib/opts.nit:213 */
+      /* ../lib/opts.nit:248 */
       fra.me.REG[4] = CALL_opts___Option___pretty(fra.me.REG[4])(fra.me.REG[4], REGB0);
       CALL_standard___file___Object___print(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[4]);
-      /* ./../lib/standard//collection//array.nit:274 */
+      /* ../lib/standard/collection/array.nit:275 */
       REGB2 = TAG_Int(1);
-      /* ./../lib/standard//kernel.nit:235 */
+      /* ../lib/standard/kernel.nit:245 */
       REGB2 = TAG_Int(UNTAG_Int(REGB1)+UNTAG_Int(REGB2));
-      /* ./../lib/standard//collection//array.nit:274 */
+      /* ../lib/standard/collection/array.nit:275 */
       REGB1 = REGB2;
     } else {
-      /* ./../lib/standard//collection//array.nit:272 */
+      /* ../lib/standard/collection/array.nit:273 */
       goto label3;
     }
   }
@@ -1529,12 +1902,13 @@ void opts___OptionContext___usage(val_t p0){
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___OptionContext___parse[] = "opts::OptionContext::parse";
 void opts___OptionContext___parse(val_t p0, val_t p1){
   struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 217;
+  fra.me.line = 252;
   fra.me.meth = LOCATE_opts___OptionContext___parse;
   fra.me.has_broke = 0;
   fra.me.REG_size = 2;
@@ -1543,61 +1917,71 @@ void opts___OptionContext___parse(val_t p0, val_t p1){
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:220 */
+  /* ../lib/opts.nit:255 */
   fra.me.REG[1] = CALL_standard___collection___abstract_collection___Collection___iterator(fra.me.REG[1])(fra.me.REG[1]);
-  /* ./../lib/opts.nit:221 */
+  /* ../lib/opts.nit:256 */
   CALL_opts___OptionContext___parse_intern(fra.me.REG[0])(fra.me.REG[0], fra.me.REG[1]);
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___OptionContext___parse_intern[] = "opts::OptionContext::parse_intern";
 void opts___OptionContext___parse_intern(val_t p0, val_t p1){
-  struct {struct stack_frame_t me; val_t MORE_REG[4];} fra;
+  struct {struct stack_frame_t me; val_t MORE_REG[6];} fra;
   val_t REGB0;
   val_t REGB1;
   val_t REGB2;
+  val_t REGB3;
+  val_t REGB4;
+  val_t REGB5;
   val_t tmp;
       static val_t once_value_1; /* Once value */
+              static val_t once_value_2; /* Once value */
+        static val_t once_value_5; /* Once value */
+        static val_t once_value_6; /* Once value */
+        static val_t once_value_7; /* Once value */
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 224;
+  fra.me.line = 259;
   fra.me.meth = LOCATE_opts___OptionContext___parse_intern;
   fra.me.has_broke = 0;
-  fra.me.REG_size = 5;
+  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;
   fra.me.REG[3] = NIT_NULL;
   fra.me.REG[4] = NIT_NULL;
+  fra.me.REG[5] = NIT_NULL;
+  fra.me.REG[6] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:226 */
-  REGB0 = TAG_Bool(true);
-  /* ./../lib/opts.nit:227 */
+  /* ../lib/opts.nit:261 */
+  REGB0 = TAG_Bool(1);
+  /* ../lib/opts.nit:262 */
   CALL_opts___OptionContext___build(fra.me.REG[0])(fra.me.REG[0]);
-  /* ./../lib/opts.nit:228 */
+  /* ../lib/opts.nit:263 */
   REGB1 = TAG_Bool(ATTR_opts___OptionContext____rest(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB1)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_rest", LOCATE_opts, 228);
+    nit_abort("Uninitialized attribute %s", "_rest", LOCATE_opts, 263);
   }
   fra.me.REG[2] = ATTR_opts___OptionContext____rest(fra.me.REG[0]);
-  /* ./../lib/opts.nit:230 */
+  /* ../lib/opts.nit:265 */
   while(1) {
     if (UNTAG_Bool(REGB0)) {
       REGB1 = CALL_standard___collection___abstract_collection___Iterator___is_ok(fra.me.REG[1])(fra.me.REG[1]);
     } else {
-      REGB2 = TAG_Bool(false);
+      REGB2 = TAG_Bool(0);
       REGB1 = REGB2;
     }
     if (UNTAG_Bool(REGB1)) {
-      /* ./../lib/opts.nit:231 */
+      /* ../lib/opts.nit:266 */
       fra.me.REG[3] = CALL_standard___collection___abstract_collection___Iterator___item(fra.me.REG[1])(fra.me.REG[1]);
-      /* ./../lib/opts.nit:232 */
+      /* ../lib/opts.nit:267 */
       if (!once_value_1) {
         fra.me.REG[4] = BOX_NativeString("--");
         REGB1 = TAG_Int(2);
-        fra.me.REG[4] = NEW_String_standard___string___String___with_native(fra.me.REG[4], REGB1);
+        fra.me.REG[4] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[4])(fra.me.REG[4], REGB1);
         once_value_1 = fra.me.REG[4];
         register_static_object(&once_value_1);
       } else fra.me.REG[4] = once_value_1;
@@ -1609,53 +1993,279 @@ void opts___OptionContext___parse_intern(val_t p0, val_t p1){
         REGB1 = REGB2;
       }
       if (UNTAG_Bool(REGB1)) {
-        /* ./../lib/opts.nit:233 */
+        /* ../lib/opts.nit:268 */
         CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[1])(fra.me.REG[1]);
-        /* ./../lib/opts.nit:234 */
+        /* ../lib/opts.nit:269 */
         fra.me.REG[4] = CALL_standard___collection___array___Iterator___to_a(fra.me.REG[1])(fra.me.REG[1]);
         CALL_standard___collection___abstract_collection___SimpleCollection___add_all(fra.me.REG[2])(fra.me.REG[2], fra.me.REG[4]);
-        /* ./../lib/opts.nit:235 */
-        REGB1 = TAG_Bool(false);
+        /* ../lib/opts.nit:270 */
+        REGB1 = TAG_Bool(0);
         REGB0 = REGB1;
       } else {
-        /* ./../lib/opts.nit:237 */
-        REGB1 = TAG_Bool(ATTR_opts___OptionContext____optmap(fra.me.REG[0])!=NIT_NULL);
-        if (UNTAG_Bool(REGB1)) {
+        /* ../lib/opts.nit:273 */
+        REGB1 = TAG_Char('-');
+        REGB1 = CALL_standard___collection___array___AbstractArrayRead___last_index_of(fra.me.REG[3])(fra.me.REG[3], REGB1);
+        REGB2 = TAG_Int(0);
+        REGB3 = TAG_Bool(IS_EQUAL_OO(REGB1,REGB2));
+        if (UNTAG_Bool(REGB3)) {
+        } else {
+          /* ../lib/standard/kernel.nit:237 */
+          REGB2 = TAG_Bool((REGB1)==(REGB2));
+          /* ../lib/opts.nit:273 */
+          REGB3 = REGB2;
+        }
+        if (UNTAG_Bool(REGB3)) {
+          /* ../lib/standard/collection/array.nit:24 */
+          REGB3 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3])!=NIT_NULL);
+          if (UNTAG_Bool(REGB3)) {
+          } else {
+            nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 24);
+          }
+          REGB3 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3]);
+          /* ../lib/opts.nit:273 */
+          REGB2 = TAG_Int(2);
+          REGB1 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB3), VTID_standard___kernel___Comparable___OTHER(REGB3))) /*cast OTHER*/;
+          if (UNTAG_Bool(REGB1)) {
+          } else {
+            nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+          }
+          /* ../lib/standard/kernel.nit:244 */
+          REGB2 = TAG_Bool(UNTAG_Int(REGB3)>UNTAG_Int(REGB2));
         } else {
-          nit_abort("Uninitialized attribute %s", "_optmap", LOCATE_opts, 237);
+          /* ../lib/opts.nit:273 */
+          REGB3 = TAG_Bool(0);
+          REGB2 = REGB3;
         }
-        fra.me.REG[4] = ATTR_opts___OptionContext____optmap(fra.me.REG[0]);
-        REGB1 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
-        if (UNTAG_Bool(REGB1)) {
-          /* ./../lib/opts.nit:238 */
-          REGB1 = TAG_Bool(ATTR_opts___OptionContext____optmap(fra.me.REG[0])!=NIT_NULL);
+        if (UNTAG_Bool(REGB2)) {
+          /* ../lib/opts.nit:274 */
+          REGB2 = TAG_Bool(0);
+          /* ../lib/opts.nit:275 */
+          REGB3 = TAG_Int(1);
+          /* ../lib/standard/collection/array.nit:24 */
+          REGB1 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3])!=NIT_NULL);
           if (UNTAG_Bool(REGB1)) {
           } else {
-            nit_abort("Uninitialized attribute %s", "_optmap", LOCATE_opts, 238);
+            nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 24);
+          }
+          REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3]);
+          /* ../lib/standard/kernel.nit:393 */
+          while(1) {
+            REGB4 = TAG_Bool(VAL_ISA(REGB1, 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:241 */
+            REGB4 = TAG_Bool(UNTAG_Int(REGB3)<=UNTAG_Int(REGB1));
+            /* ../lib/standard/kernel.nit:393 */
+            if (UNTAG_Bool(REGB4)) {
+              /* ../lib/opts.nit:275 */
+              REGB4 = REGB3;
+              /* ../lib/opts.nit:276 */
+              if (!once_value_2) {
+               fra.me.REG[4] = BOX_NativeString("-");
+               REGB5 = TAG_Int(1);
+               fra.me.REG[4] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[4])(fra.me.REG[4], REGB5);
+               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];
+              REGB4 = CALL_standard___collection___abstract_collection___SequenceRead_____bra(fra.me.REG[3])(fra.me.REG[3], REGB4);
+              fra.me.REG[5] = CALL_standard___string___Object___to_s(REGB4)(REGB4);
+              fra.me.REG[5] = CALL_standard___string___String_____plus(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
+              /* ../lib/opts.nit:277 */
+              REGB4 = TAG_Bool(ATTR_opts___OptionContext____optmap(fra.me.REG[0])!=NIT_NULL);
+              if (UNTAG_Bool(REGB4)) {
+              } else {
+               nit_abort("Uninitialized attribute %s", "_optmap", LOCATE_opts, 277);
+              }
+              fra.me.REG[4] = ATTR_opts___OptionContext____optmap(fra.me.REG[0]);
+              REGB4 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
+              if (UNTAG_Bool(REGB4)) {
+               /* ../lib/opts.nit:278 */
+               REGB4 = TAG_Bool(ATTR_opts___OptionContext____optmap(fra.me.REG[0])!=NIT_NULL);
+               if (UNTAG_Bool(REGB4)) {
+               } else {
+               nit_abort("Uninitialized attribute %s", "_optmap", LOCATE_opts, 278);
+               }
+               fra.me.REG[4] = ATTR_opts___OptionContext____optmap(fra.me.REG[0]);
+               fra.me.REG[5] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[5]);
+               /* ../lib/opts.nit:279 */
+               REGB4 = TAG_Bool(VAL_ISA(fra.me.REG[5], COLOR_opts___OptionParameter, ID_opts___OptionParameter)) /*cast OptionParameter*/;
+               if (UNTAG_Bool(REGB4)) {
+               /* ../lib/opts.nit:280 */
+               CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[1])(fra.me.REG[1]);
+               /* ../lib/opts.nit:281 */
+               REGB4 = TAG_Bool(1);
+               REGB2 = REGB4;
+               }
+               /* ../lib/opts.nit:283 */
+               CALL_opts___Option___read_param(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[1]);
+              }
+              /* ../lib/standard/kernel.nit:395 */
+              REGB4 = TAG_Int(1);
+              /* ../lib/standard/kernel.nit:245 */
+              REGB4 = TAG_Int(UNTAG_Int(REGB3)+UNTAG_Int(REGB4));
+              /* ../lib/standard/kernel.nit:395 */
+              REGB3 = REGB4;
+            } else {
+              /* ../lib/standard/kernel.nit:393 */
+              goto label3;
+            }
+          }
+          label3: while(0);
+          /* ../lib/opts.nit:286 */
+          REGB2 = TAG_Bool(!UNTAG_Bool(REGB2));
+          if (UNTAG_Bool(REGB2)) {
+            CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[1])(fra.me.REG[1]);
           }
-          fra.me.REG[4] = ATTR_opts___OptionContext____optmap(fra.me.REG[0]);
-          fra.me.REG[3] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
-          /* ./../lib/opts.nit:239 */
-          CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[1])(fra.me.REG[1]);
-          /* ./../lib/opts.nit:240 */
-          CALL_opts___Option___read_param(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
         } else {
-          /* ./../lib/opts.nit:242 */
-          fra.me.REG[3] = CALL_standard___collection___abstract_collection___Iterator___item(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[3]);
-          /* ./../lib/opts.nit:243 */
-          CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[1])(fra.me.REG[1]);
+          /* ../lib/opts.nit:288 */
+          REGB2 = TAG_Bool(ATTR_opts___OptionContext____optmap(fra.me.REG[0])!=NIT_NULL);
+          if (UNTAG_Bool(REGB2)) {
+          } else {
+            nit_abort("Uninitialized attribute %s", "_optmap", LOCATE_opts, 288);
+          }
+          fra.me.REG[5] = ATTR_opts___OptionContext____optmap(fra.me.REG[0]);
+          REGB2 = CALL_standard___collection___abstract_collection___MapRead___has_key(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[3]);
+          if (UNTAG_Bool(REGB2)) {
+            /* ../lib/opts.nit:289 */
+            REGB2 = TAG_Bool(ATTR_opts___OptionContext____optmap(fra.me.REG[0])!=NIT_NULL);
+            if (UNTAG_Bool(REGB2)) {
+            } else {
+              nit_abort("Uninitialized attribute %s", "_optmap", LOCATE_opts, 289);
+            }
+            fra.me.REG[5] = ATTR_opts___OptionContext____optmap(fra.me.REG[0]);
+            fra.me.REG[3] = CALL_standard___collection___abstract_collection___MapRead_____bra(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[3]);
+            /* ../lib/opts.nit:290 */
+            CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[1])(fra.me.REG[1]);
+            /* ../lib/opts.nit:291 */
+            CALL_opts___Option___read_param(fra.me.REG[3])(fra.me.REG[3], fra.me.REG[1]);
+          } else {
+            /* ../lib/opts.nit:293 */
+            fra.me.REG[3] = CALL_standard___collection___abstract_collection___Iterator___item(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[3]);
+            /* ../lib/opts.nit:294 */
+            CALL_standard___collection___abstract_collection___Iterator___next(fra.me.REG[1])(fra.me.REG[1]);
+          }
         }
       }
     } else {
-      /* ./../lib/opts.nit:230 */
-      goto label2;
+      /* ../lib/opts.nit:265 */
+      goto label4;
     }
   }
-  label2: while(0);
+  label4: while(0);
+  /* ../lib/opts.nit:300 */
+  REGB0 = TAG_Bool(ATTR_opts___OptionContext____options(fra.me.REG[0])!=NIT_NULL);
+  if (UNTAG_Bool(REGB0)) {
+  } else {
+    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 300);
+  }
+  fra.me.REG[1] = ATTR_opts___OptionContext____options(fra.me.REG[0]);
+  /* ../lib/standard/collection/array.nit:270 */
+  REGB0 = TAG_Int(0);
+  /* ../lib/standard/collection/array.nit:271 */
+  REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1])!=NIT_NULL);
+  if (UNTAG_Bool(REGB2)) {
+  } else {
+    nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 271);
+  }
+  REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1]);
+  /* ../lib/standard/collection/array.nit:272 */
+  fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[1]);
+  /* ../lib/standard/collection/array.nit:273 */
+  while(1) {
+    /* ../lib/standard/collection/array.nit:24 */
+    REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1])!=NIT_NULL);
+    if (UNTAG_Bool(REGB2)) {
+    } else {
+      nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 24);
+    }
+    REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1]);
+    REGB3 = TAG_Bool(VAL_ISA(REGB2, VTCOLOR_standard___kernel___Comparable___OTHER(REGB0), VTID_standard___kernel___Comparable___OTHER(REGB0))) /*cast OTHER*/;
+    if (UNTAG_Bool(REGB3)) {
+    } else {
+      nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
+    }
+    /* ../lib/standard/kernel.nit:242 */
+    REGB2 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB2));
+    /* ../lib/standard/collection/array.nit:273 */
+    if (UNTAG_Bool(REGB2)) {
+      /* ../lib/standard/collection/array.nit:274 */
+      REGB2 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+      if (UNTAG_Bool(REGB2)) {
+        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 274);
+      }
+      /* ../lib/standard/collection/array.nit:725 */
+      fra.me.REG[3] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB0)];
+      /* ../lib/opts.nit:301 */
+      REGB2 = CALL_opts___Option___mandatory(fra.me.REG[3])(fra.me.REG[3]);
+      if (UNTAG_Bool(REGB2)) {
+        REGB2 = CALL_opts___Option___read(fra.me.REG[3])(fra.me.REG[3]);
+        REGB2 = TAG_Bool(!UNTAG_Bool(REGB2));
+      } else {
+        REGB3 = TAG_Bool(0);
+        REGB2 = REGB3;
+      }
+      if (UNTAG_Bool(REGB2)) {
+        /* ../lib/opts.nit:302 */
+        REGB2 = TAG_Bool(ATTR_opts___OptionContext____errors(fra.me.REG[0])!=NIT_NULL);
+        if (UNTAG_Bool(REGB2)) {
+        } else {
+          nit_abort("Uninitialized attribute %s", "_errors", LOCATE_opts, 302);
+        }
+        fra.me.REG[5] = ATTR_opts___OptionContext____errors(fra.me.REG[0]);
+        REGB2 = TAG_Int(3);
+        fra.me.REG[4] = NEW_Array_standard___collection___array___Array___with_capacity(REGB2);
+        if (!once_value_5) {
+          fra.me.REG[6] = BOX_NativeString("Mandatory option ");
+          REGB2 = TAG_Int(17);
+          fra.me.REG[6] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[6])(fra.me.REG[6], REGB2);
+          once_value_5 = fra.me.REG[6];
+          register_static_object(&once_value_5);
+        } else fra.me.REG[6] = once_value_5;
+        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[3] = CALL_opts___Option___names(fra.me.REG[3])(fra.me.REG[3]);
+        if (!once_value_6) {
+          fra.me.REG[6] = BOX_NativeString(", ");
+          REGB2 = TAG_Int(2);
+          fra.me.REG[6] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[6])(fra.me.REG[6], REGB2);
+          once_value_6 = fra.me.REG[6];
+          register_static_object(&once_value_6);
+        } else fra.me.REG[6] = once_value_6;
+        fra.me.REG[6] = fra.me.REG[6];
+        fra.me.REG[6] = CALL_standard___string___Collection___join(fra.me.REG[3])(fra.me.REG[3], 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_7) {
+          fra.me.REG[6] = BOX_NativeString(" not found.");
+          REGB2 = TAG_Int(11);
+          fra.me.REG[6] = CALL_standard___string___NativeString___to_s_with_length(fra.me.REG[6])(fra.me.REG[6], REGB2);
+          once_value_7 = fra.me.REG[6];
+          register_static_object(&once_value_7);
+        } else fra.me.REG[6] = once_value_7;
+        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_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[5])(fra.me.REG[5], fra.me.REG[4]);
+      }
+      /* ../lib/standard/collection/array.nit:275 */
+      REGB2 = TAG_Int(1);
+      /* ../lib/standard/kernel.nit:245 */
+      REGB2 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB2));
+      /* ../lib/standard/collection/array.nit:275 */
+      REGB0 = REGB2;
+    } else {
+      /* ../lib/standard/collection/array.nit:273 */
+      goto label8;
+    }
+  }
+  label8: while(0);
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___OptionContext___add_option[] = "opts::OptionContext::add_option";
 void opts___OptionContext___add_option(val_t p0, val_t p1){
   struct {struct stack_frame_t me; val_t MORE_REG[4];} fra;
   val_t REGB0;
@@ -1664,7 +2274,7 @@ void opts___OptionContext___add_option(val_t p0, val_t p1){
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 249;
+  fra.me.line = 307;
   fra.me.meth = LOCATE_opts___OptionContext___add_option;
   fra.me.has_broke = 0;
   fra.me.REG_size = 5;
@@ -1676,27 +2286,27 @@ void opts___OptionContext___add_option(val_t p0, val_t p1){
   fra.me.REG[4] = NIT_NULL;
   fra.me.REG[0] = p0;
   fra.me.REG[1] = p1;
-  /* ./../lib/opts.nit:249 */
+  /* ../lib/opts.nit:307 */
   fra.me.REG[2] = fra.me.REG[0];
   REGB0 = TAG_Bool(VAL_ISA(fra.me.REG[1], COLOR_standard___collection___array___Array, ID_standard___collection___array___Array)) /*cast Array[Option]*/;
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Cast failed", NULL, LOCATE_opts, 249);
+    nit_abort("Cast failed", NULL, LOCATE_opts, 307);
   }
-  /* ./../lib/standard//collection//array.nit:269 */
+  /* ../lib/standard/collection/array.nit:270 */
   REGB0 = TAG_Int(0);
-  /* ./../lib/standard//collection//array.nit:270 */
+  /* ../lib/standard/collection/array.nit:271 */
   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, 270);
+    nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 271);
   }
   REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1]);
-  /* ./../lib/standard//collection//array.nit:271 */
+  /* ../lib/standard/collection/array.nit:272 */
   fra.me.REG[0] = ATTR_standard___collection___array___Array____items(fra.me.REG[1]);
-  /* ./../lib/standard//collection//array.nit:272 */
+  /* ../lib/standard/collection/array.nit:273 */
   while(1) {
-    /* ./../lib/standard//collection//array.nit:24 */
+    /* ../lib/standard/collection/array.nit:24 */
     REGB1 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1])!=NIT_NULL);
     if (UNTAG_Bool(REGB1)) {
     } else {
@@ -1708,33 +2318,33 @@ void opts___OptionContext___add_option(val_t p0, val_t p1){
     } else {
       nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
     }
-    /* ./../lib/standard//kernel.nit:232 */
+    /* ../lib/standard/kernel.nit:242 */
     REGB1 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
-    /* ./../lib/standard//collection//array.nit:272 */
+    /* ../lib/standard/collection/array.nit:273 */
     if (UNTAG_Bool(REGB1)) {
-      /* ./../lib/standard//collection//array.nit:273 */
+      /* ../lib/standard/collection/array.nit:274 */
       REGB1 = TAG_Bool(fra.me.REG[0]==NIT_NULL);
       if (UNTAG_Bool(REGB1)) {
-        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 273);
+        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 274);
       }
-      /* ./../lib/standard//collection//array.nit:718 */
+      /* ../lib/standard/collection/array.nit:725 */
       fra.me.REG[3] = ((Nit_NativeArray)fra.me.REG[0])->val[UNTAG_Int(REGB0)];
-      /* ./../lib/opts.nit:252 */
+      /* ../lib/opts.nit:310 */
       REGB1 = TAG_Bool(ATTR_opts___OptionContext____options(fra.me.REG[2])!=NIT_NULL);
       if (UNTAG_Bool(REGB1)) {
       } else {
-        nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 252);
+        nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 310);
       }
       fra.me.REG[4] = ATTR_opts___OptionContext____options(fra.me.REG[2]);
       CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[4])(fra.me.REG[4], fra.me.REG[3]);
-      /* ./../lib/standard//collection//array.nit:274 */
+      /* ../lib/standard/collection/array.nit:275 */
       REGB1 = TAG_Int(1);
-      /* ./../lib/standard//kernel.nit:235 */
+      /* ../lib/standard/kernel.nit:245 */
       REGB1 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB1));
-      /* ./../lib/standard//collection//array.nit:274 */
+      /* ../lib/standard/collection/array.nit:275 */
       REGB0 = REGB1;
     } else {
-      /* ./../lib/standard//collection//array.nit:272 */
+      /* ../lib/standard/collection/array.nit:273 */
       goto label1;
     }
   }
@@ -1742,6 +2352,7 @@ void opts___OptionContext___add_option(val_t p0, val_t p1){
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___OptionContext___init[] = "opts::OptionContext::init";
 void opts___OptionContext___init(val_t p0, int* init_table){
   int itpos9 = VAL2OBJ(p0)->vft[INIT_TABLE_POS_opts___OptionContext].i;
   struct {struct stack_frame_t me; val_t MORE_REG[1];} fra;
@@ -1749,7 +2360,7 @@ void opts___OptionContext___init(val_t p0, int* init_table){
   if (init_table[itpos9]) return;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 256;
+  fra.me.line = 314;
   fra.me.meth = LOCATE_opts___OptionContext___init;
   fra.me.has_broke = 0;
   fra.me.REG_size = 2;
@@ -1757,19 +2368,23 @@ void opts___OptionContext___init(val_t p0, int* init_table){
   fra.me.REG[0] = NIT_NULL;
   fra.me.REG[1] = NIT_NULL;
   fra.me.REG[0] = p0;
-  /* ./../lib/opts.nit:258 */
+  /* ../lib/opts.nit:316 */
   fra.me.REG[1] = NEW_Array_standard___collection___array___Array___init();
   ATTR_opts___OptionContext____options(fra.me.REG[0]) = fra.me.REG[1];
-  /* ./../lib/opts.nit:259 */
+  /* ../lib/opts.nit:317 */
   fra.me.REG[1] = NEW_HashMap_standard___collection___hash_collection___HashMap___init();
   ATTR_opts___OptionContext____optmap(fra.me.REG[0]) = fra.me.REG[1];
-  /* ./../lib/opts.nit:260 */
+  /* ../lib/opts.nit:318 */
   fra.me.REG[1] = NEW_Array_standard___collection___array___Array___init();
   ATTR_opts___OptionContext____rest(fra.me.REG[0]) = fra.me.REG[1];
+  /* ../lib/opts.nit:319 */
+  fra.me.REG[1] = NEW_Array_standard___collection___array___Array___init();
+  ATTR_opts___OptionContext____errors(fra.me.REG[0]) = fra.me.REG[1];
   stack_frame_head = fra.me.prev;
   init_table[itpos9] = 1;
   return;
 }
+static const char LOCATE_opts___OptionContext___build[] = "opts::OptionContext::build";
 void opts___OptionContext___build(val_t p0){
   struct {struct stack_frame_t me; val_t MORE_REG[7];} fra;
   val_t REGB0;
@@ -1779,7 +2394,7 @@ void opts___OptionContext___build(val_t p0){
   val_t tmp;
   fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
   fra.me.file = LOCATE_opts;
-  fra.me.line = 263;
+  fra.me.line = 322;
   fra.me.meth = LOCATE_opts___OptionContext___build;
   fra.me.has_broke = 0;
   fra.me.REG_size = 8;
@@ -1793,27 +2408,27 @@ void opts___OptionContext___build(val_t p0){
   fra.me.REG[6] = NIT_NULL;
   fra.me.REG[7] = NIT_NULL;
   fra.me.REG[0] = p0;
-  /* ./../lib/opts.nit:265 */
+  /* ../lib/opts.nit:324 */
   REGB0 = TAG_Bool(ATTR_opts___OptionContext____options(fra.me.REG[0])!=NIT_NULL);
   if (UNTAG_Bool(REGB0)) {
   } else {
-    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 265);
+    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 324);
   }
   fra.me.REG[1] = ATTR_opts___OptionContext____options(fra.me.REG[0]);
-  /* ./../lib/standard//collection//array.nit:269 */
+  /* ../lib/standard/collection/array.nit:270 */
   REGB0 = TAG_Int(0);
-  /* ./../lib/standard//collection//array.nit:270 */
+  /* ../lib/standard/collection/array.nit:271 */
   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, 270);
+    nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 271);
   }
   REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1]);
-  /* ./../lib/standard//collection//array.nit:271 */
+  /* ../lib/standard/collection/array.nit:272 */
   fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[1]);
-  /* ./../lib/standard//collection//array.nit:272 */
+  /* ../lib/standard/collection/array.nit:273 */
   while(1) {
-    /* ./../lib/standard//collection//array.nit:24 */
+    /* ../lib/standard/collection/array.nit:24 */
     REGB1 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[1])!=NIT_NULL);
     if (UNTAG_Bool(REGB1)) {
     } else {
@@ -1825,33 +2440,33 @@ void opts___OptionContext___build(val_t p0){
     } else {
       nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
     }
-    /* ./../lib/standard//kernel.nit:232 */
+    /* ../lib/standard/kernel.nit:242 */
     REGB1 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
-    /* ./../lib/standard//collection//array.nit:272 */
+    /* ../lib/standard/collection/array.nit:273 */
     if (UNTAG_Bool(REGB1)) {
-      /* ./../lib/standard//collection//array.nit:273 */
+      /* ../lib/standard/collection/array.nit:274 */
       REGB1 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
       if (UNTAG_Bool(REGB1)) {
-        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 273);
+        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 274);
       }
-      /* ./../lib/standard//collection//array.nit:718 */
+      /* ../lib/standard/collection/array.nit:725 */
       fra.me.REG[3] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB0)];
-      /* ./../lib/opts.nit:266 */
+      /* ../lib/opts.nit:325 */
       fra.me.REG[4] = CALL_opts___Option___names(fra.me.REG[3])(fra.me.REG[3]);
-      /* ./../lib/standard//collection//array.nit:269 */
+      /* ../lib/standard/collection/array.nit:270 */
       REGB1 = TAG_Int(0);
-      /* ./../lib/standard//collection//array.nit:270 */
+      /* ../lib/standard/collection/array.nit:271 */
       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, 270);
+        nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 271);
       }
       REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[4]);
-      /* ./../lib/standard//collection//array.nit:271 */
+      /* ../lib/standard/collection/array.nit:272 */
       fra.me.REG[5] = ATTR_standard___collection___array___Array____items(fra.me.REG[4]);
-      /* ./../lib/standard//collection//array.nit:272 */
+      /* ../lib/standard/collection/array.nit:273 */
       while(1) {
-        /* ./../lib/standard//collection//array.nit:24 */
+        /* ../lib/standard/collection/array.nit:24 */
         REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[4])!=NIT_NULL);
         if (UNTAG_Bool(REGB2)) {
         } else {
@@ -1863,45 +2478,45 @@ void opts___OptionContext___build(val_t p0){
         } else {
           nit_abort("Cast failed", NULL, LOCATE_standard___kernel, 0);
         }
-        /* ./../lib/standard//kernel.nit:232 */
+        /* ../lib/standard/kernel.nit:242 */
         REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
-        /* ./../lib/standard//collection//array.nit:272 */
+        /* ../lib/standard/collection/array.nit:273 */
         if (UNTAG_Bool(REGB2)) {
-          /* ./../lib/standard//collection//array.nit:273 */
+          /* ../lib/standard/collection/array.nit:274 */
           REGB2 = TAG_Bool(fra.me.REG[5]==NIT_NULL);
           if (UNTAG_Bool(REGB2)) {
-            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 273);
+            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 274);
           }
-          /* ./../lib/standard//collection//array.nit:718 */
+          /* ../lib/standard/collection/array.nit:725 */
           fra.me.REG[6] = ((Nit_NativeArray)fra.me.REG[5])->val[UNTAG_Int(REGB1)];
-          /* ./../lib/opts.nit:267 */
+          /* ../lib/opts.nit:326 */
           REGB2 = TAG_Bool(ATTR_opts___OptionContext____optmap(fra.me.REG[0])!=NIT_NULL);
           if (UNTAG_Bool(REGB2)) {
           } else {
-            nit_abort("Uninitialized attribute %s", "_optmap", LOCATE_opts, 267);
+            nit_abort("Uninitialized attribute %s", "_optmap", LOCATE_opts, 326);
           }
           fra.me.REG[7] = ATTR_opts___OptionContext____optmap(fra.me.REG[0]);
           CALL_standard___collection___abstract_collection___Map_____braeq(fra.me.REG[7])(fra.me.REG[7], fra.me.REG[6], fra.me.REG[3]);
-          /* ./../lib/standard//collection//array.nit:274 */
+          /* ../lib/standard/collection/array.nit:275 */
           REGB2 = TAG_Int(1);
-          /* ./../lib/standard//kernel.nit:235 */
+          /* ../lib/standard/kernel.nit:245 */
           REGB2 = TAG_Int(UNTAG_Int(REGB1)+UNTAG_Int(REGB2));
-          /* ./../lib/standard//collection//array.nit:274 */
+          /* ../lib/standard/collection/array.nit:275 */
           REGB1 = REGB2;
         } else {
-          /* ./../lib/standard//collection//array.nit:272 */
+          /* ../lib/standard/collection/array.nit:273 */
           goto label1;
         }
       }
       label1: while(0);
-      /* ./../lib/standard//collection//array.nit:274 */
+      /* ../lib/standard/collection/array.nit:275 */
       REGB1 = TAG_Int(1);
-      /* ./../lib/standard//kernel.nit:235 */
+      /* ../lib/standard/kernel.nit:245 */
       REGB1 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB1));
-      /* ./../lib/standard//collection//array.nit:274 */
+      /* ../lib/standard/collection/array.nit:275 */
       REGB0 = REGB1;
     } else {
-      /* ./../lib/standard//collection//array.nit:272 */
+      /* ../lib/standard/collection/array.nit:273 */
       goto label2;
     }
   }
@@ -1909,3 +2524,148 @@ void opts___OptionContext___build(val_t p0){
   stack_frame_head = fra.me.prev;
   return;
 }
+static const char LOCATE_opts___OptionContext___get_errors[] = "opts::OptionContext::get_errors";
+val_t opts___OptionContext___get_errors(val_t p0){
+  struct {struct stack_frame_t me; val_t MORE_REG[5];} fra;
+  val_t REGB0;
+  val_t REGB1;
+  val_t REGB2;
+  val_t REGB3;
+  val_t tmp;
+  fra.me.prev = stack_frame_head; stack_frame_head = &fra.me;
+  fra.me.file = LOCATE_opts;
+  fra.me.line = 331;
+  fra.me.meth = LOCATE_opts___OptionContext___get_errors;
+  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;
+  fra.me.REG[3] = NIT_NULL;
+  fra.me.REG[4] = NIT_NULL;
+  fra.me.REG[5] = NIT_NULL;
+  fra.me.REG[0] = p0;
+  /* ../lib/opts.nit:333 */
+  fra.me.REG[1] = NEW_Array_standard___collection___array___Array___init();
+  /* ../lib/opts.nit:335 */
+  REGB0 = TAG_Bool(ATTR_opts___OptionContext____errors(fra.me.REG[0])!=NIT_NULL);
+  if (UNTAG_Bool(REGB0)) {
+  } else {
+    nit_abort("Uninitialized attribute %s", "_errors", LOCATE_opts, 335);
+  }
+  fra.me.REG[2] = ATTR_opts___OptionContext____errors(fra.me.REG[0]);
+  CALL_standard___collection___abstract_collection___SimpleCollection___add_all(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[2]);
+  /* ../lib/opts.nit:337 */
+  REGB0 = TAG_Bool(ATTR_opts___OptionContext____options(fra.me.REG[0])!=NIT_NULL);
+  if (UNTAG_Bool(REGB0)) {
+  } else {
+    nit_abort("Uninitialized attribute %s", "_options", LOCATE_opts, 337);
+  }
+  fra.me.REG[0] = ATTR_opts___OptionContext____options(fra.me.REG[0]);
+  /* ../lib/standard/collection/array.nit:270 */
+  REGB0 = TAG_Int(0);
+  /* ../lib/standard/collection/array.nit:271 */
+  REGB1 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[0])!=NIT_NULL);
+  if (UNTAG_Bool(REGB1)) {
+  } else {
+    nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 271);
+  }
+  REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[0]);
+  /* ../lib/standard/collection/array.nit:272 */
+  fra.me.REG[2] = ATTR_standard___collection___array___Array____items(fra.me.REG[0]);
+  /* ../lib/standard/collection/array.nit:273 */
+  while(1) {
+    /* ../lib/standard/collection/array.nit:24 */
+    REGB1 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[0])!=NIT_NULL);
+    if (UNTAG_Bool(REGB1)) {
+    } else {
+      nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 24);
+    }
+    REGB1 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[0]);
+    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:242 */
+    REGB1 = TAG_Bool(UNTAG_Int(REGB0)<UNTAG_Int(REGB1));
+    /* ../lib/standard/collection/array.nit:273 */
+    if (UNTAG_Bool(REGB1)) {
+      /* ../lib/standard/collection/array.nit:274 */
+      REGB1 = TAG_Bool(fra.me.REG[2]==NIT_NULL);
+      if (UNTAG_Bool(REGB1)) {
+        nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 274);
+      }
+      /* ../lib/standard/collection/array.nit:725 */
+      fra.me.REG[3] = ((Nit_NativeArray)fra.me.REG[2])->val[UNTAG_Int(REGB0)];
+      /* ../lib/opts.nit:338 */
+      fra.me.REG[3] = CALL_opts___Option___errors(fra.me.REG[3])(fra.me.REG[3]);
+      /* ../lib/standard/collection/array.nit:270 */
+      REGB1 = TAG_Int(0);
+      /* ../lib/standard/collection/array.nit:271 */
+      REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3])!=NIT_NULL);
+      if (UNTAG_Bool(REGB2)) {
+      } else {
+        nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 271);
+      }
+      REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3]);
+      /* ../lib/standard/collection/array.nit:272 */
+      fra.me.REG[4] = ATTR_standard___collection___array___Array____items(fra.me.REG[3]);
+      /* ../lib/standard/collection/array.nit:273 */
+      while(1) {
+        /* ../lib/standard/collection/array.nit:24 */
+        REGB2 = TAG_Bool(ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3])!=NIT_NULL);
+        if (UNTAG_Bool(REGB2)) {
+        } else {
+          nit_abort("Uninitialized attribute %s", "_length", LOCATE_standard___collection___array, 24);
+        }
+        REGB2 = ATTR_standard___collection___array___AbstractArrayRead____length(fra.me.REG[3]);
+        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:242 */
+        REGB2 = TAG_Bool(UNTAG_Int(REGB1)<UNTAG_Int(REGB2));
+        /* ../lib/standard/collection/array.nit:273 */
+        if (UNTAG_Bool(REGB2)) {
+          /* ../lib/standard/collection/array.nit:274 */
+          REGB2 = TAG_Bool(fra.me.REG[4]==NIT_NULL);
+          if (UNTAG_Bool(REGB2)) {
+            nit_abort("Reciever is null", NULL, LOCATE_standard___collection___array, 274);
+          }
+          /* ../lib/standard/collection/array.nit:725 */
+          fra.me.REG[5] = ((Nit_NativeArray)fra.me.REG[4])->val[UNTAG_Int(REGB1)];
+          /* ../lib/opts.nit:339 */
+          CALL_standard___collection___abstract_collection___SimpleCollection___add(fra.me.REG[1])(fra.me.REG[1], fra.me.REG[5]);
+          /* ../lib/standard/collection/array.nit:275 */
+          REGB2 = TAG_Int(1);
+          /* ../lib/standard/kernel.nit:245 */
+          REGB2 = TAG_Int(UNTAG_Int(REGB1)+UNTAG_Int(REGB2));
+          /* ../lib/standard/collection/array.nit:275 */
+          REGB1 = REGB2;
+        } else {
+          /* ../lib/standard/collection/array.nit:273 */
+          goto label1;
+        }
+      }
+      label1: while(0);
+      /* ../lib/standard/collection/array.nit:275 */
+      REGB1 = TAG_Int(1);
+      /* ../lib/standard/kernel.nit:245 */
+      REGB1 = TAG_Int(UNTAG_Int(REGB0)+UNTAG_Int(REGB1));
+      /* ../lib/standard/collection/array.nit:275 */
+      REGB0 = REGB1;
+    } else {
+      /* ../lib/standard/collection/array.nit:273 */
+      goto label2;
+    }
+  }
+  label2: while(0);
+  /* ../lib/opts.nit:343 */
+  goto label3;
+  label3: while(0);
+  stack_frame_head = fra.me.prev;
+  return fra.me.REG[1];
+}