| /*============================================================================= | |
| Copyright (c) 2001-2006 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(BOOST_FUSION_AT_IMPL_09262006_1920) | |
| #define BOOST_FUSION_AT_IMPL_09262006_1920 | |
| #include <boost/tuple/tuple.hpp> | |
| #include <boost/mpl/if.hpp> | |
| namespace boost { namespace fusion | |
| { | |
| struct boost_tuple_tag; | |
| namespace extension | |
| { | |
| template<typename T> | |
| struct at_impl; | |
| template <> | |
| struct at_impl<boost_tuple_tag> | |
| { | |
| template <typename Sequence, typename N> | |
| struct apply | |
| { | |
| typedef typename | |
| tuples::element<N::value, Sequence>::type | |
| element; | |
| typedef typename | |
| mpl::if_< | |
| is_const<Sequence> | |
| , typename tuples::access_traits<element>::const_type | |
| , typename tuples::access_traits<element>::non_const_type | |
| >::type | |
| type; | |
| static type | |
| call(Sequence& seq) | |
| { | |
| return tuples::get<N::value>(seq); | |
| } | |
| }; | |
| }; | |
| } | |
| }} | |
| #endif |