Fix map check expression

README.md

@@ -34,7 +34,6 @@ When developping/debugging, I'm running `gi` on a single script, using `-a` and
 - [ ] diagnostics and proper error handling
 - [ ] named output variables (test/ret1.gi)
 - [ ] defer
-- [ ] blank
 - [ ] ellipsis
 - [ ] method calls from runtime to interpreter
 - [ ] forward declarations

_test/map5.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+func main() {
+	dict := map[string]string{"bidule": "machin", "truc": "bidule"}
+	r, ok := dict["xxx"]
+	fmt.Println(r, ok)
+}
+
+// Output:
+//  false

interp/cfg.go

@@ -242,7 +242,8 @@ func (interp *Interpreter) Cfg(root *Node, sdef *NodeMap) []*Node {
 			if n.kind == DefineX {
 				// retrieve assigned value types from call signature
 				var types []*Type
-				if n.child[l].kind == CallExpr {
+				switch n.child[l].kind {
+				case CallExpr:
 					if funtype := n.child[l].child[0].typ; funtype.cat == ValueT {
 						// Handle functions imported from runtime
 						for i := 0; i < funtype.rtype.NumOut(); i++ {
@@ -251,6 +252,10 @@ func (interp *Interpreter) Cfg(root *Node, sdef *NodeMap) []*Node {
 					} else {
 						types = funtype.ret
 					}
+				case TypeAssertExpr, IndexExpr:
+					types = append(types, n.child[l].child[1].typ, defaultTypes["error"])
+				default:
+					log.Fatalln(n.index, "Assign expression unsupported:", n.child[l].kind)
 				}
 				// Force definition of assigned idents in current scope
 				for i, c := range n.child[:l] {
@@ -273,6 +278,7 @@ func (interp *Interpreter) Cfg(root *Node, sdef *NodeMap) []*Node {
 			n.typ = n.child[0].typ.val
 			n.recv = n
 			if n.child[0].typ.cat == MapT {
+				frameIndex.max++ // Reserve an entry for getIndexMap 2nd return value
 				n.run = getIndexMap
 			}
 
@@ -834,6 +840,18 @@ func getDefault(n *Node) int {
 	return -1
 }
 
+// isType returns true if node refers to a type definition, false otherwise
+func (n *Node) isType() bool {
+	switch n.kind {
+	case ArrayType, ChanType, FuncType, MapType, StructType:
+		return true
+	case Ident:
+		_, ok := n.interp.types[n.ident]
+		return ok
+	}
+	return false
+}
+
 // Wire AST nodes for CFG in subtree
 func wireChild(n *Node) {
 	// Set start node, in subtree (propagated to ancestors by post-order processing)

interp/interp_test.go

@@ -1075,6 +1075,26 @@ func main() {
 	// bonjour
 }
 
+func Example_map5() {
+	src := `
+package main
+
+import "fmt"
+
+func main() {
+	dict := map[string]string{"bidule": "machin", "truc": "bidule"}
+	r, ok := dict["xxx"]
+	fmt.Println(r, ok)
+}
+`
+	i := NewInterpreter(Opt{Entry: "main"})
+	i.ImportBin(export.Pkg)
+	i.Eval(src)
+
+	// Output:
+	//  false
+}
+
 func Example_math0() {
 	src := `
 package main

interp/run.go

@@ -401,7 +401,7 @@ func callBinMethod(n *Node, f *Frame) {
 			in[i+1] = reflect.ValueOf(value(c, f))
 		}
 	}
-	log.Println(n.index, "in callBinMethod", n.ident, in, in[0].MethodByName(n.child[0].child[1].ident).Type())
+	//log.Println(n.index, "in callBinMethod", n.ident, in, in[0].MethodByName(n.child[0].child[1].ident).Type())
 	if !fun.IsValid() {
 		fun = in[0].MethodByName(n.child[0].child[1].ident)
 		in = in[1:]
@@ -464,7 +464,10 @@ func getIndex(n *Node, f *Frame) {
 
 func getIndexMap(n *Node, f *Frame) {
 	m := value(n.child[0], f).(map[interface{}]interface{})
-	f.data[n.findex] = m[value(n.child[1], f)]
+	if f.data[n.findex], f.data[n.findex+1] = m[value(n.child[1], f)]; !f.data[n.findex+1].(bool) {
+		// Force a zero value if key is not present in map
+		f.data[n.findex] = n.child[0].typ.val.zero()
+	}
 }
 
 func getMap(n *Node, f *Frame) {