ceph/src/boost/boost/fusion/iterator/prior.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_PRIOR_05042005_1144)
   8 #define FUSION_PRIOR_05042005_1144
   9
  10 #include <boost/fusion/support/config.hpp>
  11 #include <boost/fusion/support/tag_of.hpp>
  12
  13 namespace boost { namespace fusion
  14 {
  15     // Special tags:
  16     struct iterator_facade_tag; // iterator facade tag
  17     struct boost_array_iterator_tag; // boost::array iterator tag
  18     struct mpl_iterator_tag; // mpl sequence iterator tag
  19     struct std_pair_iterator_tag; // std::pair iterator tag
  20
  21     namespace extension
  22     {
  23         template <typename Tag>
  24         struct prior_impl
  25         {
  26             template <typename Iterator>
  27             struct apply {};
  28         };
  29
  30         template <>
  31         struct prior_impl<iterator_facade_tag>
  32         {
  33             template <typename Iterator>
  34             struct apply : Iterator::template prior<Iterator> {};
  35         };
  36
  37         template <>
  38         struct prior_impl<boost_array_iterator_tag>;
  39
  40         template <>
  41         struct prior_impl<mpl_iterator_tag>;
  42
  43         template <>
  44         struct prior_impl<std_pair_iterator_tag>;
  45     }
  46
  47     namespace result_of
  48     {
  49         template <typename Iterator>
  50         struct prior
  51             : extension::prior_impl<typename detail::tag_of<Iterator>::type>::
  52                 template apply<Iterator>
  53         {};
  54     }
  55
  56     template <typename Iterator>
  57     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  58     inline typename result_of::prior<Iterator>::type const
  59     prior(Iterator const& i)
  60     {
  61         return result_of::prior<Iterator>::call(i);
  62     }
  63 }}
  64
  65 #endif