boost/spirit/home/qi/reference.hpp
/*=============================================================================
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_REFERENCE_OCTOBER_31_2008_1218AM)
#define BOOST_SPIRIT_REFERENCE_OCTOBER_31_2008_1218AM
#if defined(_MSC_VER)
#pragma once
#endif
#include <boost/spirit/home/qi/meta_compiler.hpp>
#include <boost/spirit/home/qi/parser.hpp>
#include <boost/spirit/home/support/info.hpp>
#include <boost/spirit/home/support/handles_container.hpp>
#include <boost/type_traits/remove_const.hpp>
#include <boost/ref.hpp>
namespace boost { namespace spirit { namespace qi
{
///////////////////////////////////////////////////////////////////////////
// reference is a parser that references another parser (its Subject)
///////////////////////////////////////////////////////////////////////////
template <typename Subject>
struct reference : parser<reference<Subject> >
{
typedef Subject subject_type;
reference(Subject& subject)
: ref(subject) {}
template <typename Context, typename Iterator>
struct attribute : Subject::template attribute<Context, Iterator> {};
template <typename Iterator, typename Context
, typename Skipper, typename Attribute>
bool parse(Iterator& first, Iterator const& last
, Context& context, Skipper const& skipper
, Attribute& attr_) const
{
return ref.get().parse(first, last, context, skipper, attr_);
}
template <typename Context>
info what(Context& context) const
{
// the reference is transparent (does not add any info)
return ref.get().what(context);
}
boost::reference_wrapper<Subject> ref;
};
}}}
namespace boost { namespace spirit { namespace traits
{
///////////////////////////////////////////////////////////////////////////
template <typename Subject, typename Attribute, typename Context
, typename Iterator>
struct handles_container<qi::reference<Subject>, Attribute, Context
, Iterator>
: handles_container<typename remove_const<Subject>::type
, Attribute, Context, Iterator>
{};
}}}
#endif