/*============================================================================= | |
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_EQUAL_TO_05052005_1208) | |
#define FUSION_EQUAL_TO_05052005_1208 | |
#include <boost/type_traits/is_same.hpp> | |
#include <boost/fusion/support/tag_of.hpp> | |
#include <boost/type_traits/add_const.hpp> | |
#include <boost/fusion/support/is_iterator.hpp> | |
#include <boost/mpl/and.hpp> | |
#include <boost/utility/enable_if.hpp> | |
namespace boost { namespace fusion | |
{ | |
// 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 equal_to_impl | |
{ | |
// default implementation | |
template <typename I1, typename I2> | |
struct apply | |
: is_same<typename add_const<I1>::type, typename add_const<I2>::type> | |
{}; | |
}; | |
template <> | |
struct equal_to_impl<iterator_facade_tag> | |
{ | |
template <typename I1, typename I2> | |
struct apply : I1::template equal_to<I1, I2> {}; | |
}; | |
template <> | |
struct equal_to_impl<boost_array_iterator_tag>; | |
template <> | |
struct equal_to_impl<mpl_iterator_tag>; | |
template <> | |
struct equal_to_impl<std_pair_iterator_tag>; | |
} | |
namespace result_of | |
{ | |
template <typename I1, typename I2> | |
struct equal_to | |
: extension::equal_to_impl<typename detail::tag_of<I1>::type>:: | |
template apply<I1, I2> | |
{}; | |
} | |
namespace iterator_operators | |
{ | |
template <typename Iter1, typename Iter2> | |
inline typename | |
enable_if< | |
mpl::and_<is_fusion_iterator<Iter1>, is_fusion_iterator<Iter2> > | |
, bool | |
>::type | |
operator==(Iter1 const&, Iter2 const&) | |
{ | |
return result_of::equal_to<Iter1, Iter2>::value; | |
} | |
template <typename Iter1, typename Iter2> | |
inline typename | |
enable_if< | |
mpl::and_<is_fusion_iterator<Iter1>, is_fusion_iterator<Iter2> > | |
, bool | |
>::type | |
operator!=(Iter1 const&, Iter2 const&) | |
{ | |
return !result_of::equal_to<Iter1, Iter2>::value; | |
} | |
} | |
using iterator_operators::operator==; | |
using iterator_operators::operator!=; | |
}} | |
#endif | |