3rdparty/boost/boost/fusion/container/list/cons_iterator.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 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_CONS_ITERATOR_07172005_0849)
   9 #define FUSION_CONS_ITERATOR_07172005_0849
  10
  11 #include <boost/fusion/support/config.hpp>
  12 #include <boost/type_traits/add_const.hpp>
  13 #include <boost/fusion/support/iterator_base.hpp>
  14 #include <boost/fusion/container/list/detail/deref_impl.hpp>
  15 #include <boost/fusion/container/list/detail/next_impl.hpp>
  16 #include <boost/fusion/container/list/detail/value_of_impl.hpp>
  17 #include <boost/fusion/container/list/detail/equal_to_impl.hpp>
  18 #include <boost/fusion/container/list/list_fwd.hpp>
  19
  20 namespace boost { namespace fusion
  21 {
  22     struct nil_;
  23     struct cons_iterator_tag;
  24     struct forward_traversal_tag;
  25
  26     template <typename Cons>
  27     struct cons_iterator_identity;
  28
  29     template <typename Cons = nil_>
  30     struct cons_iterator : iterator_base<cons_iterator<Cons> >
  31     {
  32         typedef cons_iterator_tag fusion_tag;
  33         typedef forward_traversal_tag category;
  34         typedef Cons cons_type;
  35         typedef cons_iterator_identity<
  36             typename add_const<Cons>::type>
  37         identity;
  38
  39         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  40         explicit cons_iterator(cons_type& in_cons) BOOST_NOEXCEPT
  41             : cons(in_cons) {}
  42
  43         cons_type& cons;
  44
  45     private:
  46         // silence MSVC warning C4512: assignment operator could not be generated
  47         cons_iterator& operator= (cons_iterator const&);
  48     };
  49
  50     struct nil_iterator : iterator_base<nil_iterator>
  51     {
  52         typedef forward_traversal_tag category;
  53         typedef cons_iterator_tag fusion_tag;
  54         typedef nil_ cons_type;
  55         typedef cons_iterator_identity<
  56             add_const<nil_>::type>
  57         identity;
  58
  59         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  60         nil_iterator() BOOST_NOEXCEPT {}
  61         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  62         explicit nil_iterator(nil_ const&) BOOST_NOEXCEPT {}
  63     };
  64
  65     template <>
  66     struct cons_iterator<nil_> : nil_iterator
  67     {
  68         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  69         cons_iterator() BOOST_NOEXCEPT {}
  70         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  71         explicit cons_iterator(nil_ const&) BOOST_NOEXCEPT {}
  72     };
  73
  74     template <>
  75     struct cons_iterator<nil_ const> : nil_iterator
  76     {
  77         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  78         cons_iterator() BOOST_NOEXCEPT {}
  79         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  80         explicit cons_iterator(nil_ const&) BOOST_NOEXCEPT {}
  81     };
  82
  83     template <>
  84     struct cons_iterator<list<> > : nil_iterator
  85     {
  86         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  87         cons_iterator() BOOST_NOEXCEPT {}
  88         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  89         explicit cons_iterator(nil_ const&) BOOST_NOEXCEPT {}
  90     };
  91
  92     template <>
  93     struct cons_iterator<list<> const> : nil_iterator
  94     {
  95         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  96         cons_iterator() BOOST_NOEXCEPT {}
  97         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  98         explicit cons_iterator(nil_ const&) BOOST_NOEXCEPT {}
  99     };
 100 }}
 101
 102 #ifdef BOOST_FUSION_WORKAROUND_FOR_LWG_2408
 103 namespace std
 104 {
 105     template <typename Cons>
 106     struct iterator_traits< ::boost::fusion::cons_iterator<Cons> >
 107     { };
 108 }
 109 #endif
 110
 111 #endif