/*============================================================================= Copyright (c) 2001-2011 Joel de Guzman Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) ==============================================================================*/ #if !defined(FUSION_DISTANCE_09172005_0721) #define FUSION_DISTANCE_09172005_0721 #include <boost/fusion/support/config.hpp> #include <boost/fusion/iterator/detail/distance.hpp> #include <boost/fusion/support/category_of.hpp> #include <boost/mpl/int.hpp> #include <boost/mpl/assert.hpp> #include <boost/type_traits/is_same.hpp> #include <boost/fusion/support/tag_of.hpp> namespace boost { namespace fusion { struct random_access_traversal_tag; // Special tags: struct iterator_facade_tag; // iterator facade tag struct boost_array_iterator_tag; // boost::array iterator tag struct mpl_iterator_tag; // mpl sequence iterator tag struct std_pair_iterator_tag; // std::pair iterator tag namespace extension { template <typename Tag> struct distance_impl { // default implementation template <typename First, typename Last> struct apply : distance_detail::linear_distance<First, Last> {}; }; template <> struct distance_impl<iterator_facade_tag> { template <typename First, typename Last> struct apply : First::template distance<First, Last> {}; }; template <> struct distance_impl<boost_array_iterator_tag>; template <> struct distance_impl<mpl_iterator_tag>; template <> struct distance_impl<std_pair_iterator_tag>; } namespace result_of { template <typename First, typename Last> struct distance : extension::distance_impl<typename detail::tag_of<First>::type>:: template apply<First, Last> { typedef typename extension::distance_impl<typename detail::tag_of<First>::type>:: template apply<First, Last>::type distance_application; BOOST_STATIC_CONSTANT(int, value = distance_application::value); }; } template <typename First, typename Last> BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED inline typename result_of::distance<First, Last>::type distance(First const& a, Last const& b) { return result_of::distance<First, Last>::call(a,b); } }} #endif