Chris@16: /*=============================================================================
Chris@16:     Copyright (c) 2001-2011 Joel de Guzman
Chris@16: 
Chris@16:     Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16:     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: =============================================================================*/
Chris@16: #if !defined(SPIRIT_OMIT_MARCH_24_2007_0802AM)
Chris@16: #define SPIRIT_OMIT_MARCH_24_2007_0802AM
Chris@16: 
Chris@16: #if defined(_MSC_VER)
Chris@16: #pragma once
Chris@16: #endif
Chris@16: 
Chris@16: #include <boost/spirit/home/qi/meta_compiler.hpp>
Chris@16: #include <boost/spirit/home/qi/skip_over.hpp>
Chris@16: #include <boost/spirit/home/qi/parser.hpp>
Chris@16: #include <boost/spirit/home/support/unused.hpp>
Chris@16: #include <boost/spirit/home/support/info.hpp>
Chris@16: #include <boost/spirit/home/support/common_terminals.hpp>
Chris@16: #include <boost/spirit/home/support/has_semantic_action.hpp>
Chris@16: #include <boost/spirit/home/support/handles_container.hpp>
Chris@16: 
Chris@16: namespace boost { namespace spirit
Chris@16: {
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // Enablers
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <>
Chris@16:     struct use_directive<qi::domain, tag::omit> // enables omit
Chris@16:       : mpl::true_ {};
Chris@16: }}
Chris@16: 
Chris@16: namespace boost { namespace spirit { namespace qi
Chris@16: {
Chris@16: #ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
Chris@16:     using spirit::omit;
Chris@16: #endif
Chris@16:     using spirit::omit_type;
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // omit_directive forces the attribute of subject parser
Chris@16:     // to be unused_type
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename Subject>
Chris@16:     struct omit_directive : unary_parser<omit_directive<Subject> >
Chris@16:     {
Chris@16:         typedef Subject subject_type;
Chris@16:         omit_directive(Subject const& subject_)
Chris@16:           : subject(subject_) {}
Chris@16: 
Chris@16:         template <typename Context, typename Iterator>
Chris@16:         struct attribute
Chris@16:         {
Chris@16:             typedef unused_type type;
Chris@16:         };
Chris@16: 
Chris@16:         template <typename Iterator, typename Context
Chris@16:           , typename Skipper, typename Attribute>
Chris@16:         bool parse(Iterator& first, Iterator const& last
Chris@16:           , Context& context, Skipper const& skipper, Attribute& attr_) const
Chris@16:         {
Chris@16:             return subject.parse(first, last, context, skipper, attr_);
Chris@16:         }
Chris@16: 
Chris@16:         template <typename Context>
Chris@16:         info what(Context& context) const
Chris@16:         {
Chris@16:             return info("omit", subject.what(context));
Chris@16:         }
Chris@16: 
Chris@16:         Subject subject;
Chris@16: 
Chris@16:     private:
Chris@16:         // silence MSVC warning C4512: assignment operator could not be generated
Chris@16:         omit_directive& operator= (omit_directive const&);
Chris@16:     };
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // Parser generators: make_xxx function (objects)
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename Subject, typename Modifiers>
Chris@16:     struct make_directive<tag::omit, Subject, Modifiers>
Chris@16:     {
Chris@16:         typedef omit_directive<Subject> result_type;
Chris@16:         result_type operator()(unused_type, Subject const& subject, unused_type) const
Chris@16:         {
Chris@16:             return result_type(subject);
Chris@16:         }
Chris@16:     };
Chris@16: }}}
Chris@16: 
Chris@16: namespace boost { namespace spirit { namespace traits
Chris@16: {
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename Subject>
Chris@16:     struct has_semantic_action<qi::omit_directive<Subject> >
Chris@16:       : mpl::false_ {};
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename Subject, typename Attribute, typename Context
Chris@16:         , typename Iterator>
Chris@16:     struct handles_container<qi::omit_directive<Subject>, Attribute
Chris@16:         , Context, Iterator>
Chris@16:       : unary_handles_container<Subject, Attribute, Context, Iterator> {};
Chris@16: }}}
Chris@16: 
Chris@16: #endif