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/*=============================================================================
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
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