Chris@16: /*=============================================================================
Chris@16:     Copyright (c) 2001-2011 Joel de Guzman
Chris@16: 
Chris@16:     Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16:     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: ==============================================================================*/
Chris@16: #if !defined(FUSION_ADVANCE_09172005_1146)
Chris@16: #define FUSION_ADVANCE_09172005_1146
Chris@16: 
Chris@101: #include <boost/fusion/support/config.hpp>
Chris@16: #include <boost/fusion/iterator/detail/advance.hpp>
Chris@16: #include <boost/fusion/support/category_of.hpp>
Chris@16: 
Chris@16: #include <boost/mpl/int.hpp>
Chris@16: #include <boost/mpl/assert.hpp>
Chris@16: #include <boost/type_traits/is_same.hpp>
Chris@16: #include <boost/fusion/support/tag_of.hpp>
Chris@16: 
Chris@16: namespace boost { namespace fusion
Chris@16: {
Chris@16:     struct random_access_traversal_tag;
Chris@16: 
Chris@16:     // Special tags:
Chris@16:     struct iterator_facade_tag; // iterator facade tag
Chris@16:     struct boost_array_iterator_tag; // boost::array iterator tag
Chris@16:     struct mpl_iterator_tag; // mpl sequence iterator tag
Chris@16:     struct std_pair_iterator_tag; // std::pair iterator tag
Chris@16: 
Chris@16:     namespace extension
Chris@16:     {
Chris@16:         template <typename Tag>
Chris@16:         struct advance_impl
Chris@16:         {
Chris@16:             // default implementation
Chris@16:             template <typename Iterator, typename N>
Chris@16:             struct apply :
Chris@16:                 mpl::if_c<
Chris@16:                     (N::value > 0)
Chris@16:                   , advance_detail::forward<Iterator, N::value>
Chris@16:                   , advance_detail::backward<Iterator, N::value>
Chris@16:                 >::type
Chris@16:             {
Chris@16:                 BOOST_MPL_ASSERT_NOT((traits::is_random_access<Iterator>));
Chris@16:             };
Chris@16:         };
Chris@16: 
Chris@16:         template <>
Chris@16:         struct advance_impl<iterator_facade_tag>
Chris@16:         {
Chris@16:             template <typename Iterator, typename N>
Chris@16:             struct apply : Iterator::template advance<Iterator, N> {};
Chris@16:         };
Chris@16: 
Chris@16:         template <>
Chris@16:         struct advance_impl<boost_array_iterator_tag>;
Chris@16: 
Chris@16:         template <>
Chris@16:         struct advance_impl<mpl_iterator_tag>;
Chris@16: 
Chris@16:         template <>
Chris@16:         struct advance_impl<std_pair_iterator_tag>;
Chris@16:     }
Chris@16: 
Chris@16:     namespace result_of
Chris@16:     {
Chris@16:         template <typename Iterator, int N>
Chris@16:         struct advance_c
Chris@16:             : extension::advance_impl<typename detail::tag_of<Iterator>::type>::template apply<Iterator, mpl::int_<N> >
Chris@16:         {};
Chris@16: 
Chris@16:         template <typename Iterator, typename N>
Chris@16:         struct advance
Chris@16:             : extension::advance_impl<typename detail::tag_of<Iterator>::type>::template apply<Iterator, N>
Chris@16:         {};
Chris@16:     }
Chris@16: 
Chris@16:     template <int N, typename Iterator>
Chris@101:     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
Chris@16:     inline typename result_of::advance_c<Iterator, N>::type const
Chris@16:     advance_c(Iterator const& i)
Chris@16:     {
Chris@16:         return result_of::advance_c<Iterator, N>::call(i);
Chris@16:     }
Chris@16: 
Chris@16:     template<typename N, typename Iterator>
Chris@101:     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
Chris@16:     inline typename result_of::advance<Iterator, N>::type const
Chris@16:     advance(Iterator const& i)
Chris@16:     {
Chris@16:         return result_of::advance<Iterator, N>::call(i);
Chris@16:     }
Chris@16: 
Chris@16: }} // namespace boost::fusion
Chris@16: 
Chris@16: #endif