/*=============================================================================
    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(FUSION_VALUE_AT_IMPL_07172005_0952)
#define FUSION_VALUE_AT_IMPL_07172005_0952

#include <boost/fusion/support/config.hpp>
#include <boost/fusion/support/detail/access.hpp>
#include <boost/type_traits/is_const.hpp>
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/bool.hpp>

namespace boost {
namespace fusion {
struct cons_tag;

namespace extension {
template <typename Tag>
struct value_at_impl;

template <>
struct value_at_impl<cons_tag>
{
    template <typename Sequence, typename N>
    struct apply
    {
        typedef typename
        mpl::eval_if<
        mpl::bool_<N::value == 0>
        , mpl::identity<typename Sequence::car_type>
        , apply<typename Sequence::cdr_type, mpl::int_<N::value-1> >
        >::type
        type;
    };
};
}
}
}

#endif
