ceph/src/boost/libs/fusion/include/boost/fusion/support/is_view.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 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(FUSION_IS_VIEW_03202006_0015)
   8 #define FUSION_IS_VIEW_03202006_0015
   9
  10 #include <boost/fusion/support/config.hpp>
  11 #include <boost/mpl/bool.hpp>
  12 #include <boost/fusion/support/detail/is_view.hpp>
  13 #include <boost/fusion/support/tag_of.hpp>
  14
  15 namespace boost { namespace fusion
  16 {
  17     // Special tags:
  18     struct sequence_facade_tag;
  19     struct boost_tuple_tag; // boost::tuples::tuple tag
  20     struct boost_array_tag; // boost::array tag
  21     struct mpl_sequence_tag; // mpl sequence tag
  22     struct std_pair_tag; // std::pair tag
  23
  24     namespace extension
  25     {
  26         template<typename Tag>
  27         struct is_view_impl
  28         {
  29             template <typename T>
  30             struct apply
  31                 : detail::fusion_is_view<T>
  32             {};
  33         };
  34
  35         template <>
  36         struct is_view_impl<sequence_facade_tag>
  37         {
  38             template <typename Sequence>
  39             struct apply : Sequence::is_view {};
  40         };
  41
  42         template <>
  43         struct is_view_impl<boost_tuple_tag>;
  44
  45         template <>
  46         struct is_view_impl<boost_array_tag>;
  47
  48         template <>
  49         struct is_view_impl<mpl_sequence_tag>;
  50
  51         template <>
  52         struct is_view_impl<std_pair_tag>;
  53     }
  54
  55     namespace traits
  56     {
  57         template <typename T>
  58         struct is_view :
  59             mpl::bool_<
  60                 (bool)extension::is_view_impl<typename fusion::detail::tag_of<T>::type>::
  61                     template apply<T>::type::value
  62             >
  63         {};
  64     }
  65 }}
  66
  67 #endif