boost/fusion/view/nview/detail/advance_impl.hpp

   1 /*=============================================================================
   2     Copyright (c) 2009 Hartmut Kaiser
   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
   8 #if !defined(BOOST_FUSION_NVIEW_ADVANCE_IMPL_SEP_24_2009_0212PM)
   9 #define BOOST_FUSION_NVIEW_ADVANCE_IMPL_SEP_24_2009_0212PM
  10
  11 #include <boost/fusion/support/config.hpp>
  12 #include <boost/mpl/advance.hpp>
  13 #include <boost/fusion/iterator/advance.hpp>
  14
  15 namespace boost { namespace fusion
  16 {
  17     struct nview_iterator_tag;
  18
  19     template <typename Sequence, typename Pos>
  20     struct nview_iterator;
  21
  22     namespace extension
  23     {
  24         template<typename Tag>
  25         struct advance_impl;
  26
  27         template<>
  28         struct advance_impl<nview_iterator_tag>
  29         {
  30             template<typename Iterator, typename Dist>
  31             struct apply
  32             {
  33                 typedef typename Iterator::first_type::iterator_type iterator_type;
  34                 typedef typename Iterator::sequence_type sequence_type;
  35
  36                 typedef nview_iterator<sequence_type,
  37                     typename mpl::advance<iterator_type, Dist>::type> type;
  38
  39                 BOOST_FUSION_GPU_ENABLED
  40                 static type
  41                 call(Iterator const& i)
  42                 {
  43                     return type(i.seq);
  44                 }
  45             };
  46         };
  47     }
  48
  49 }}
  50
  51 #endif