else if (cur_tok.is_lbracket()) {
                eat_token();
                auto& arr_sub_node = create_ast_node<ast_arr_subscript>();
                arr_sub_node.arr_name = id_name;
                if ((arr_sub_node.subscript_expr = parse_expr(-1))) {
                    if (cur_tok.is_rbracket()) {
                        eat_token();
                        return &arr_sub_node;
                    }
                }
            }