basic for loop + examples -> era3

core/vm.go

@@ -133,6 +133,9 @@ const (
 	// InstructionFormTuple pop n+1 (u16) items from the stack, and create a new tuple with the items. The top value
 	// on the stack is the last value in the tuple.
 	InstructionFormTuple
+	// InstructionDestructureTuple pop a tuple, and push all its items to the stack, with the top item on the stack
+	// being the last item in the tuple.
+	InstructionDestructureTuple
 
 	// InstructionIndexList index into a list. The lower item is the container, and the top item
 	// is the index. [..., container, index] -> [..., item]
@@ -251,6 +254,8 @@ func (b Bytecode) String() string {
 		return "INDEX_LIST"
 	case InstructionIndexTuple:
 		return "INDEX_TUPLE"
+	case InstructionDestructureTuple:
+		return "DESTRUCTURE_TUPLE"
 	}
 	return "UNDEFINED"
 }
@@ -605,10 +610,7 @@ var DefaultGlobals = map[string]Value{
 					&StringSignature{},
 				),
 			},
-			quickComposite(
-				&FloatSignature{},
-				&NilSignature{},
-			),
+			&FloatSignature{},
 		},
 		func(vm *VM, _ Value, args []Value) (Value, error) {
 			switch v := args[0].(type) {
@@ -620,7 +622,7 @@ var DefaultGlobals = map[string]Value{
 			case *StringValue:
 				num, err := strconv.ParseFloat(v.Text, FloatSize)
 				if err != nil {
-					return &NilValue{}, nil
+					return &FloatValue{}, nil
 				}
 
 				return &FloatValue{num}, nil
@@ -1014,6 +1016,11 @@ func (vm *VM) Next() bool {
 			items,
 		})
 
+	case InstructionDestructureTuple:
+		t := vm.Stack.Pop().(*TupleValue)
+
+		vm.Stack.Push(t.Items...)
+
 	case InstructionDescend:
 		vm.descend()