Merge: Safe call operator

[nit.git] / src / interpreter / naive_interpreter.nit

diff --git a/src/interpreter/naive_interpreter.nit b/src/interpreter/naive_interpreter.nit
index 9c7ec34..233d758 100644 (file)
--- a/src/interpreter/naive_interpreter.nit
+++ b/src/interpreter/naive_interpreter.nit
@@ -721,6 +721,10 @@ abstract class Instance
        # Abort if the instance is not a boolean value.
        fun is_true: Bool do abort
 
+       # Return `true` if the instance is null.
+       # Return `false` otherwise.
+       fun is_null: Bool do return mtype isa MNullType
+
        # Return true if `self` IS `o` (using the Nit semantic of is)
        fun eq_is(o: Instance): Bool do return self.is_same_instance(o)
 
@@ -1529,7 +1533,7 @@ redef class AAttrPropdef
                else if mpropdef == mwritepropdef then
                        assert args.length == 2
                        var arg = args[1]
-                       if is_optional and arg.mtype isa MNullType then
+                       if is_optional and arg.is_null then
                                var f = v.new_frame(self, mpropdef, args)
                                arg = evaluate_expr(v, recv, f)
                        end
@@ -1824,7 +1828,7 @@ redef class AForExpr
                for g in n_groups do
                        var col = v.expr(g.n_expr)
                        if col == null then return
-                       if col.mtype isa MNullType then fatal(v, "Receiver is null")
+                       if col.is_null then fatal(v, "Receiver is null")
 
                        var iter = v.callsite(g.method_iterator, [col]).as(not null)
                        iters.add iter
@@ -1991,8 +1995,9 @@ end
 redef class ACharExpr
        redef fun expr(v)
        do
-               if is_ascii then return v.int_instance(self.value.as(not null).ascii)
-               if is_code_point then return v.int_instance(self.value.as(not null).code_point)
+               if is_code_point then
+                       return v.int_instance(self.value.as(not null).code_point)
+               end
                return v.char_instance(self.value.as(not null))
        end
 end
@@ -2184,7 +2189,7 @@ redef class AAsNotnullExpr
        do
                var i = v.expr(self.n_expr)
                if i == null then return null
-               if i.mtype isa MNullType then
+               if i.is_null then
                        fatal(v, "Cast failed")
                end
                return i
@@ -2217,6 +2222,12 @@ redef class ASendExpr
        do
                var recv = v.expr(self.n_expr)
                if recv == null then return null
+
+               # Safe call shortcut if recv is null
+               if is_safe and recv.is_null then
+                       return recv
+               end
+
                var args = v.varargize(callsite.mpropdef, callsite.signaturemap, recv, self.raw_arguments)
                if args == null then return null
 
@@ -2313,7 +2324,7 @@ redef class AAttrExpr
        do
                var recv = v.expr(self.n_expr)
                if recv == null then return null
-               if recv.mtype isa MNullType then fatal(v, "Receiver is null")
+               if recv.is_null then fatal(v, "Receiver is null")
                var mproperty = self.mproperty.as(not null)
                return v.read_attribute(mproperty, recv)
        end
@@ -2324,7 +2335,7 @@ redef class AAttrAssignExpr
        do
                var recv = v.expr(self.n_expr)
                if recv == null then return
-               if recv.mtype isa MNullType then fatal(v, "Receiver is null")
+               if recv.is_null then fatal(v, "Receiver is null")
                var i = v.expr(self.n_value)
                if i == null then return
                var mproperty = self.mproperty.as(not null)
@@ -2337,7 +2348,7 @@ redef class AAttrReassignExpr
        do
                var recv = v.expr(self.n_expr)
                if recv == null then return
-               if recv.mtype isa MNullType then fatal(v, "Receiver is null")
+               if recv.is_null then fatal(v, "Receiver is null")
                var value = v.expr(self.n_value)
                if value == null then return
                var mproperty = self.mproperty.as(not null)
@@ -2353,7 +2364,7 @@ redef class AIssetAttrExpr
        do
                var recv = v.expr(self.n_expr)
                if recv == null then return null
-               if recv.mtype isa MNullType then fatal(v, "Receiver is null")
+               if recv.is_null then fatal(v, "Receiver is null")
                var mproperty = self.mproperty.as(not null)
                return v.bool_instance(v.isset_attribute(mproperty, recv))
        end
@@ -2366,6 +2377,13 @@ redef class AVarargExpr
        end
 end
 
+redef class ASafeExpr
+       redef fun expr(v)
+       do
+               return v.expr(self.n_expr)
+       end
+end
+
 redef class ANamedargExpr
        redef fun expr(v)
        do