boost/fusion/container/list/detail/end_impl.hpp

   1 /*=============================================================================
   2     Copyright (c) 2005 Joel de Guzman
   3     Copyright (c) 2005 Eric Niebler
   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(FUSION_END_IMPL_07172005_0828)
   9 #define FUSION_END_IMPL_07172005_0828
  10
  11 #include <boost/mpl/if.hpp>
  12 #include <boost/type_traits/is_const.hpp>
  13
  14 namespace boost { namespace fusion
  15 {
  16     struct nil;
  17
  18     struct cons_tag;
  19
  20     template <typename Car, typename Cdr>
  21     struct cons;
  22
  23     template <typename Cons>
  24     struct cons_iterator;
  25
  26     namespace extension
  27     {
  28         template <typename Tag>
  29         struct end_impl;
  30
  31         template <>
  32         struct end_impl<cons_tag>
  33         {
  34             template <typename Sequence>
  35             struct apply
  36             {
  37                 typedef cons_iterator<
  38                     typename mpl::if_<is_const<Sequence>, nil const, nil>::type>
  39                 type;
  40
  41                 static type
  42                 call(Sequence&)
  43                 {
  44                     return type();
  45                 }
  46             };
  47         };
  48     }
  49 }}
  50
  51 #endif