simpler vm

internal/object/array.go

@@ -70,31 +70,33 @@ func (ao *Array) Less(i, j int) bool {
 	return false
 }
 
-func (ao *Array) Add(other Object) (Object, error) {
-	if other.Type() != ao.Type() {
-		return nil, NewBinaryOpError(ao, other, "+")
+func (a *Array) Add(other Object) (Object, error) {
+	switch obj := other.(type) {
+	case *Array:
+		var elements []Object
+		elements = append(elements, a.Elements...)
+		elements = append(elements, obj.Elements...)
+
+		return &Array{Elements: elements}, nil
+	default:
+		return nil, NewBinaryOpError(a, other, "+")
 	}
-
-	var elements []Object
-	elements = append(elements, ao.Elements...)
-	elements = append(elements, other.(*Array).Elements...)
-
-	return &Array{Elements: elements}, nil
-
 }
 
-func (ao *Array) Mul(other Object) (Object, error) {
-	if other.Type() != IntegerType {
-		return nil, NewBinaryOpError(ao, other, "*")
+func (a *Array) Mul(other Object) (Object, error) {
+	switch obj := other.(type) {
+	case Integer:
+		var elements []Object
+		N := int(obj.Value)
+		for i := 0; i < N; i++ {
+			elements = append(elements, a.Elements...)
+		}
+
+		return &Array{Elements: elements}, nil
+	default:
+		return nil, NewBinaryOpError(a, other, "*")
 	}
 
-	var elements []Object
-	N := int(other.(Integer).Value)
-	for i := 0; i < N; i++ {
-		elements = append(elements, ao.Elements...)
-	}
-
-	return &Array{Elements: elements}, nil
 }
 
 func (ao *Array) Get(index Object) (Object, error) {