nview/detail/begin_impl.hpp

0001 /*=============================================================================
0002     Copyright (c) 2009 Hartmut Kaiser
0003
0004     Distributed under the Boost Software License, Version 1.0. (See accompanying
0005     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0006 ==============================================================================*/
0007
0008 #if !defined(BOOST_FUSION_NVIEW_BEGIN_IMPL_SEP_23_2009_1036PM)
0009 #define BOOST_FUSION_NVIEW_BEGIN_IMPL_SEP_23_2009_1036PM
0010
0011 #include <boost/fusion/support/config.hpp>
0012 #include <boost/fusion/sequence/intrinsic/begin.hpp>
0013
0014 namespace boost { namespace fusion
0015 {
0016     struct nview_tag;
0017
0018     template <typename Sequence, typename Pos>
0019     struct nview_iterator;
0020
0021     namespace extension
0022     {
0023         template<typename Tag>
0024         struct begin_impl;
0025
0026         template<>
0027         struct begin_impl<nview_tag>
0028         {
0029             template<typename Sequence>
0030             struct apply
0031             {
0032                 typedef typename Sequence::index_type index_type;
0033
0034                 typedef nview_iterator<Sequence,
0035                     typename result_of::begin<index_type>::type> type;
0036
0037                 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
0038                 static type call(Sequence& s)
0039                 {
0040                     return type(s);
0041                 }
0042             };
0043         };
0044     }
0045
0046 }}
0047
0048 #endif
0049