always.hpp
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#ifndef BOOST_METAPARSE_V1_ALWAYS_HPP
#define BOOST_METAPARSE_V1_ALWAYS_HPP
// Copyright Abel Sinkovics (abel@sinkovics.hu) 2009 - 2010.
// 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)
#include <boost/metaparse/v1/accept.hpp>
#include <boost/metaparse/v1/is_error.hpp>
#include <boost/metaparse/v1/get_remaining.hpp>
#include <boost/metaparse/v1/get_position.hpp>
#include <boost/mpl/eval_if.hpp>
namespace boost
{
namespace metaparse
{
namespace v1
{
template <class P, class Result>
struct always
{
private:
template <class Res>
struct apply_unchecked :
accept<
Result,
typename get_remaining<Res>::type,
typename get_position<Res>::type
>
{};
public:
typedef always type;
template <class S, class Pos>
struct apply :
boost::mpl::eval_if<
typename is_error<typename P::template apply<S, Pos> >::type,
typename P::template apply<S, Pos>,
apply_unchecked<typename P::template apply<S, Pos> >
>
{};
};
}
}
}
#endif