| /*============================================================================= |
| Copyright (c) 2001-2011 Joel de Guzman |
| |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| ==============================================================================*/ |
| #if !defined(BOOST_SPIRIT_PARSER_BINDER_DECEMBER_05_2008_0516_PM) |
| #define BOOST_SPIRIT_PARSER_BINDER_DECEMBER_05_2008_0516_PM |
| |
| #if defined(_MSC_VER) |
| #pragma once |
| #endif |
| |
| #include <boost/fusion/include/at.hpp> |
| #include <boost/mpl/bool.hpp> |
| #include <boost/spirit/home/support/has_semantic_action.hpp> |
| |
| namespace boost { namespace spirit { namespace qi { namespace detail |
| { |
| // parser_binder for plain rules |
| template <typename Parser, typename Auto> |
| struct parser_binder |
| { |
| parser_binder(Parser const& p) |
| : p(p) {} |
| |
| template <typename Iterator, typename Skipper, typename Context> |
| bool call(Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper, mpl::true_) const |
| { |
| // If DeducedAuto is false (semantic actions is present), the |
| // component's attribute is unused. |
| return p.parse(first, last, context, skipper, unused); |
| } |
| |
| template <typename Iterator, typename Skipper, typename Context> |
| bool call(Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper, mpl::false_) const |
| { |
| // If DeducedAuto is true (no semantic action), we pass the rule's |
| // attribute on to the component. |
| return p.parse(first, last, context, skipper |
| , fusion::at_c<0>(context.attributes)); |
| } |
| |
| template <typename Iterator, typename Skipper, typename Context> |
| bool operator()( |
| Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper) const |
| { |
| // If Auto is false, we need to deduce whether to apply auto rule |
| typedef typename traits::has_semantic_action<Parser>::type auto_rule; |
| return call(first, last, context, skipper, auto_rule()); |
| } |
| |
| Parser p; |
| }; |
| |
| // parser_binder for auto rules |
| template <typename Parser> |
| struct parser_binder<Parser, mpl::true_> |
| { |
| parser_binder(Parser const& p) |
| : p(p) {} |
| |
| template <typename Iterator, typename Skipper, typename Context> |
| bool operator()( |
| Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper) const |
| { |
| // If Auto is true, we pass the rule's attribute on to the component. |
| return p.parse(first, last, context, skipper |
| , fusion::at_c<0>(context.attributes)); |
| } |
| |
| Parser p; |
| }; |
| |
| template <typename Auto, typename Parser> |
| inline parser_binder<Parser, Auto> |
| bind_parser(Parser const& p) |
| { |
| return parser_binder<Parser, Auto>(p); |
| } |
| }}}} |
| |
| #endif |