RefPtr<Expression> parse_expression(const Operator * = 0);
RefPtr<Literal> parse_literal();
RefPtr<BinaryExpression> parse_binary(const RefPtr<Expression> &, const Operator &);
RefPtr<Expression> parse_expression(const Operator * = 0);
RefPtr<Literal> parse_literal();
RefPtr<BinaryExpression> parse_binary(const RefPtr<Expression> &, const Operator &);