ceph/src/boost/boost/fusion/container/map/detail/at_impl.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2013 Joel de Guzman
   3
   4     Distributed under the Boost Software License, Version 1.0. (See accompanying
   5     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 ==============================================================================*/
   7 #if !defined(BOOST_FUSION_MAP_DETAIL_AT_IMPL_02042013_0821)
   8 #define BOOST_FUSION_MAP_DETAIL_AT_IMPL_02042013_0821
   9
  10 #include <boost/fusion/support/config.hpp>
  11 #include <boost/fusion/support/detail/access.hpp>
  12 #include <boost/utility/declval.hpp>
  13
  14 namespace boost { namespace fusion
  15 {
  16     struct map_tag;
  17
  18     namespace extension
  19     {
  20         template <typename Tag>
  21         struct at_impl;
  22
  23         template <>
  24         struct at_impl<map_tag>
  25         {
  26             template <typename Sequence, typename N>
  27             struct apply
  28             {
  29                 typedef mpl::int_<N::value> index;
  30                 typedef
  31                     decltype(boost::declval<Sequence>().get(index()))
  32                 type;
  33
  34                 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  35                 static type
  36                 call(Sequence& m)
  37                 {
  38                     return m.get(index());
  39                 }
  40             };
  41
  42             template <typename Sequence, typename N>
  43             struct apply<Sequence const, N>
  44             {
  45                 typedef mpl::int_<N::value> index;
  46                 typedef
  47                     decltype(boost::declval<Sequence const>().get(index()))
  48                 type;
  49
  50                 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  51                 static type
  52                 call(Sequence const& m)
  53                 {
  54                     return m.get(index());
  55                 }
  56             };
  57         };
  58     }
  59 }}
  60
  61 #endif