%PDF- %PDF-
| Direktori : /usr/include/boost/metaparse/v1/cpp98/impl/ |
| Current File : //usr/include/boost/metaparse/v1/cpp98/impl/nth_of_c_impl.hpp |
#ifndef BOOST_METAPARSE_V1_CPP98_IMPL_NTH_OF_C_IMPL_HPP
#define BOOST_METAPARSE_V1_CPP98_IMPL_NTH_OF_C_IMPL_HPP
// Copyright Abel Sinkovics (abel@sinkovics.hu) 2013.
// 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/cpp98/impl/skip_seq.hpp>
#include <boost/mpl/front.hpp>
#include <boost/mpl/pop_front.hpp>
#include <boost/mpl/fold.hpp>
namespace boost
{
namespace metaparse
{
namespace v1
{
namespace impl
{
template <int N, class Seq>
struct nth_of_c_impl
{
private:
template <class NextResult>
struct apply_unchecked :
nth_of_c_impl<
N - 1,
typename boost::mpl::pop_front<Seq>::type
>::template apply<
typename get_remaining<NextResult>::type,
typename get_position<NextResult>::type
>
{};
public:
typedef nth_of_c_impl type;
template <class S, class Pos>
struct apply :
boost::mpl::eval_if<
typename is_error<
typename boost::mpl::front<Seq>::type::template apply<S, Pos>
>::type,
typename boost::mpl::front<Seq>::type::template apply<S, Pos>,
apply_unchecked<
typename boost::mpl::front<Seq>::type::template apply<S, Pos>
>
>
{};
};
template <class Seq>
struct nth_of_c_impl<0, Seq>
{
typedef nth_of_c_impl type;
template <class S, class Pos>
struct apply :
boost::mpl::fold<
typename boost::mpl::pop_front<Seq>::type,
typename boost::mpl::front<Seq>::type::template apply<
S,
Pos
>::type,
skip_seq
>
{};
};
}
}
}
}
#endif