ceph/src/boost/libs/fusion/include/boost/fusion/view/filter_view/detail/next_impl.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_NEXT_IMPL_06052005_0900)
   8 #define FUSION_NEXT_IMPL_06052005_0900
   9
  10 #include <boost/fusion/support/config.hpp>
  11 #include <boost/fusion/algorithm/query/detail/find_if.hpp>
  12 #include <boost/fusion/iterator/value_of.hpp>
  13 #include <boost/mpl/eval_if.hpp>
  14 #include <boost/mpl/identity.hpp>
  15 #include <boost/mpl/lambda.hpp>
  16 #include <boost/mpl/quote.hpp>
  17 #include <boost/mpl/bind.hpp>
  18 #include <boost/mpl/placeholders.hpp>
  19
  20 namespace boost { namespace fusion
  21 {
  22     struct filter_view_iterator_tag;
  23
  24     template <typename Category,  typename First, typename Last, typename Pred>
  25     struct filter_iterator;
  26
  27     namespace extension
  28     {
  29         template <typename Tag>
  30         struct next_impl;
  31
  32         template <>
  33         struct next_impl<filter_view_iterator_tag>
  34         {
  35             template <typename Iterator>
  36             struct apply
  37             {
  38                 typedef typename Iterator::first_type first_type;
  39                 typedef typename Iterator::last_type last_type;
  40                 typedef typename Iterator::pred_type pred_type;
  41                 typedef typename Iterator::category category;
  42
  43                 typedef typename
  44                     mpl::eval_if<
  45                         result_of::equal_to<first_type, last_type>
  46                       , mpl::identity<last_type>
  47                       , result_of::next<first_type>
  48                     >::type
  49                 next_type;
  50
  51                 typedef typename
  52                     detail::static_find_if<
  53                         next_type
  54                       , last_type
  55                       , mpl::bind1<
  56                             typename mpl::lambda<pred_type>::type
  57                           , mpl::bind1<mpl::quote1<result_of::value_of>,mpl::_1>
  58                         >
  59                     >
  60                 filter;
  61
  62                 typedef filter_iterator<
  63                     category, typename filter::type, last_type, pred_type>
  64                 type;
  65
  66                 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  67                 static type
  68                 call(Iterator const& i)
  69                 {
  70                     return type(filter::iter_call(i.first));
  71                 }
  72             };
  73         };
  74     }
  75 }}
  76
  77 #endif
  78
  79