def arg_list(self, ending_char=TokenTypes.RPAREN):
        """
        arglist    : expression, arglist
        arglist    : expression
        arglist    :
        """
        args = []
        while not self.cur_token.type == ending_char:
            args.append(self.expression())
            if self.cur_token.type == TokenTypes.COMMA:
                self.eat(TokenTypes.COMMA)

        return args
arglist    : expression, arglist
        arglist    : expression
        arglist    :