sequence/intrinsic/swap.hpp

0001 /*=============================================================================
0002     Copyright (c) 2001-2011 Joel de Guzman
0003     Copyright (c) 2006 Dan Marsden
0004
0005     Distributed under the Boost Software License, Version 1.0. (See accompanying
0006     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0007 ==============================================================================*/
0008 #if !defined(BOOST_FUSION_SWAP_20070501_1956)
0009 #define BOOST_FUSION_SWAP_20070501_1956
0010
0011 #include <boost/fusion/support/config.hpp>
0012 #include <algorithm>
0013
0014 #include <boost/fusion/support/is_sequence.hpp>
0015 #include <boost/fusion/view/zip_view.hpp>
0016 #include <boost/fusion/algorithm/iteration/for_each.hpp>
0017 #include <boost/fusion/sequence/intrinsic/front.hpp>
0018 #include <boost/fusion/sequence/intrinsic/back.hpp>
0019 #include <boost/core/enable_if.hpp>
0020 #include <boost/mpl/and.hpp>
0021
0022 namespace boost { namespace fusion {
0023
0024     namespace result_of
0025     {
0026         template<typename Seq1, typename Seq2>
0027         struct swap
0028             : enable_if<mpl::and_<
0029                   traits::is_sequence<Seq1>,
0030                   traits::is_sequence<Seq2>
0031               > > {};
0032     }
0033
0034     namespace detail
0035     {
0036         struct swap
0037         {
0038             template<typename Elem>
0039             struct result
0040             {
0041                 typedef void type;
0042             };
0043
0044             template<typename Elem>
0045             BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
0046             void operator()(Elem const& e) const
0047             {
0048                 using std::swap;
0049                 swap(front(e), back(e));
0050             }
0051         };
0052     }
0053
0054     template<typename Seq1, typename Seq2>
0055     BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
0056     inline typename result_of::swap<Seq1, Seq2>::type
0057     swap(Seq1& lhs, Seq2& rhs)
0058     {
0059         typedef vector<Seq1&, Seq2&> references;
0060         for_each(zip_view<references>(references(lhs, rhs)), detail::swap());
0061     }
0062 }}
0063
0064 #endif