Switched to pointer receivers for values

src/core/CompileAssign.go

@@ -36,9 +36,9 @@ func (f *Function) CompileAssign(node *ast.Assign) error {
 	operation := node.Expression.Token
 
 	switch leftValue := leftValue.(type) {
-	case eval.Register:
+	case *eval.Register:
 		f.Execute(operation, leftValue.Register, right)
-	case eval.Memory:
+	case *eval.Memory:
 		if operation.Kind == token.Assign {
 			rightValue, err := f.Evaluate(right)