/*============================================================================= | |
Copyright (c) 2001-2006 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_ADVANCE_09172005_1146) | |
#define FUSION_ADVANCE_09172005_1146 | |
#include <boost/fusion/iterator/detail/advance.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 advance_impl | |
{ | |
// default implementation | |
template <typename Iterator, typename N> | |
struct apply : | |
mpl::if_c< | |
(N::value > 0) | |
, advance_detail::forward<Iterator, N::value> | |
, advance_detail::backward<Iterator, N::value> | |
>::type | |
{ | |
BOOST_MPL_ASSERT_NOT((traits::is_random_access<Iterator>)); | |
}; | |
}; | |
template <> | |
struct advance_impl<iterator_facade_tag> | |
{ | |
template <typename Iterator, typename N> | |
struct apply : Iterator::template advance<Iterator, N> {}; | |
}; | |
template <> | |
struct advance_impl<boost_array_iterator_tag>; | |
template <> | |
struct advance_impl<mpl_iterator_tag>; | |
template <> | |
struct advance_impl<std_pair_iterator_tag>; | |
} | |
namespace result_of | |
{ | |
template <typename Iterator, int N> | |
struct advance_c | |
: extension::advance_impl<typename detail::tag_of<Iterator>::type>::template apply<Iterator, mpl::int_<N> > | |
{}; | |
template <typename Iterator, typename N> | |
struct advance | |
: extension::advance_impl<typename detail::tag_of<Iterator>::type>::template apply<Iterator, N> | |
{}; | |
} | |
template <int N, typename Iterator> | |
inline typename result_of::advance_c<Iterator, N>::type const | |
advance_c(Iterator const& i) | |
{ | |
return result_of::advance_c<Iterator, N>::call(i); | |
} | |
template<typename N, typename Iterator> | |
inline typename result_of::advance<Iterator, N>::type const | |
advance(Iterator const& i) | |
{ | |
return result_of::advance<Iterator, N>::call(i); | |
} | |
}} // namespace boost::fusion | |
#endif |