fusion/sequence/convert.hpp

0001 /*=============================================================================
0002     Copyright (c) 2001-2011 Joel de Guzman
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 #if !defined(FUSION_CONVERT_10022005_1442)
0008 #define FUSION_CONVERT_10022005_1442
0009
0010 #include <boost/fusion/support/config.hpp>
0011 #if BOOST_WORKAROUND(BOOST_GCC, < 30500)
0012 #include <boost/core/enable_if.hpp>
0013 #include <boost/type_traits/is_const.hpp>
0014 #define BOOST_FUSION_WA_GCC34(type1, type2) \
0015     boost::lazy_disable_if<boost::is_const<Sequence>, type1, type2>
0016 #else
0017 #define BOOST_FUSION_WA_GCC34(type1, type2) type1, type2
0018 #endif
0019
0020 namespace boost { namespace fusion
0021 {
0022     namespace extension
0023     {
0024         template <typename Tag>
0025         struct convert_impl;
0026     }
0027
0028     namespace result_of
0029     {
0030         template <typename Tag, typename Sequence>
0031         struct convert
0032         {
0033             typedef typename
0034                 extension::convert_impl<Tag>::template apply<Sequence>
0035             gen;
0036
0037             typedef typename gen::type type;
0038         };
0039     }
0040
0041     template <typename Tag, typename Sequence>
0042     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
0043     inline typename BOOST_FUSION_WA_GCC34(result_of::convert<Tag, Sequence>)::type
0044     convert(Sequence& seq)
0045     {
0046         typedef typename result_of::convert<Tag, Sequence>::gen gen;
0047         return gen::call(seq);
0048     }
0049
0050     template <typename Tag, typename Sequence>
0051     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
0052     inline typename result_of::convert<Tag, Sequence const>::type
0053     convert(Sequence const& seq)
0054     {
0055         typedef typename result_of::convert<Tag, Sequence const>::gen gen;
0056         return gen::call(seq);
0057     }
0058 }}
0059
0060 #undef BOOST_FUSION_WA_GCC34
0061 #endif