forked from boostorg/fusion
82 lines
2.1 KiB
C++
82 lines
2.1 KiB
C++
|
/*=============================================================================
|
||
|
|
Copyright (c) 2001-2006 Joel de Guzman
|
||
|
|
|
||
|
|
Use, modification and distribution is subject to 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_AT_05042005_0722)
|
||
|
|
#define FUSION_AT_05042005_0722
|
||
|
|
|
||
|
|
#include <boost/mpl/int.hpp>
|
||
|
|
#include <boost/type_traits/is_const.hpp>
|
||
|
|
#include <boost/fusion/support/tag_of.hpp>
|
||
|
|
#include <boost/fusion/support/detail/access.hpp>
|
||
|
|
|
||
|
|
namespace boost { namespace fusion
|
||
|
|
{
|
||
|
|
namespace extension
|
||
|
|
{
|
||
|
|
template <typename Tag>
|
||
|
|
struct at_impl
|
||
|
|
{
|
||
|
|
template <typename Sequence, typename N>
|
||
|
|
struct apply;
|
||
|
|
};
|
||
|
|
}
|
||
|
|
|
||
|
|
namespace result_of
|
||
|
|
{
|
||
|
|
template <typename Sequence, typename N>
|
||
|
|
struct at
|
||
|
|
: extension::at_impl<typename detail::tag_of<Sequence>::type>::
|
||
|
|
template apply<Sequence, N>
|
||
|
|
{};
|
||
|
|
|
||
|
|
template <typename Sequence, int N>
|
||
|
|
struct at_c
|
||
|
|
: at<Sequence, mpl::int_<N> >
|
||
|
|
{};
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
template <typename N, typename Sequence>
|
||
|
|
inline typename
|
||
|
|
lazy_disable_if<
|
||
|
|
is_const<Sequence>
|
||
|
|
, result_of::at<Sequence, N>
|
||
|
|
>::type
|
||
|
|
at(Sequence& seq)
|
||
|
|
{
|
||
|
|
return result_of::at<Sequence, N>::call(seq);
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename N, typename Sequence>
|
||
|
|
inline typename result_of::at<Sequence const, N>::type
|
||
|
|
at(Sequence const& seq)
|
||
|
|
{
|
||
|
|
return result_of::at<Sequence const, N>::call(seq);
|
||
|
|
}
|
||
|
|
|
||
|
|
template <int N, typename Sequence>
|
||
|
|
inline typename
|
||
|
|
lazy_disable_if<
|
||
|
|
is_const<Sequence>
|
||
|
|
, result_of::at_c<Sequence, N>
|
||
|
|
>::type
|
||
|
|
at_c(Sequence& seq)
|
||
|
|
{
|
||
|
|
return at<mpl::int_<N> >(seq);
|
||
|
|
}
|
||
|
|
|
||
|
|
template <int N, typename Sequence>
|
||
|
|
inline typename result_of::at_c<Sequence const, N>::type
|
||
|
|
at_c(Sequence const& seq)
|
||
|
|
{
|
||
|
|
return at<mpl::int_<N> >(seq);
|
||
|
|
}
|
||
|
|
}}
|
||
|
|
|
||
|
|
#endif
|
||
|
|
|