ceph/src/boost/libs/fusion/include/boost/fusion/adapted/mpl/detail/category_of_impl.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Joel de Guzman
   3     Copyright (c) 2005-2006 Dan Marsden
   4
   5     Distributed under the Boost Software License, Version 1.0. (See accompanying
   6     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   7 ==============================================================================*/
   8 #if !defined(BOOST_FUSION_CATEGORY_OF_IMPL_20060217_2141)
   9 #define BOOST_FUSION_CATEGORY_OF_IMPL_20060217_2141
  10
  11 #include <boost/fusion/support/config.hpp>
  12 #include <boost/fusion/support/detail/mpl_iterator_category.hpp>
  13 #include <boost/mpl/begin_end.hpp>
  14 #include <boost/mpl/is_sequence.hpp>
  15 #include <boost/static_assert.hpp>
  16
  17 namespace boost { namespace fusion {
  18
  19     namespace detail
  20     {
  21         template <typename T>
  22         struct mpl_sequence_category_of
  23         {
  24             // assumes T is an mpl sequence
  25             // there should be no way this will ever be
  26             // called where T is an mpl iterator
  27
  28             BOOST_STATIC_ASSERT(mpl::is_sequence<T>::value);
  29             typedef typename
  30                 mpl_iterator_category<
  31                     typename mpl::begin<T>::type::category
  32                 >::type
  33             type;
  34         };
  35     }
  36
  37     struct mpl_sequence_tag;
  38
  39     namespace extension
  40     {
  41         template<typename Tag>
  42         struct category_of_impl;
  43
  44         template<>
  45         struct category_of_impl<mpl_sequence_tag>
  46         {
  47             template<typename T>
  48             struct apply
  49                 : detail::mpl_sequence_category_of<T>
  50             {};
  51         };
  52     }
  53 }}
  54
  55 #endif