// Boost.Range library
//
//  Copyright Neil Groves 2010. Use, modification and
//  distribution is subject to 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)
//
// For more information, see http://www.boost.org/libs/range/
//
// Acknowledgments:
// Ticket #8341: Arno Schoedl - improved handling of has_range_iterator upon
// use-cases where T was const.
#ifndef BOOST_RANGE_HAS_ITERATOR_HPP_INCLUDED
#define BOOST_RANGE_HAS_ITERATOR_HPP_INCLUDED

#include <boost/mpl/bool.hpp>
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/has_xxx.hpp>
#include <boost/range/iterator.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/utility/enable_if.hpp>

namespace boost {
namespace range_detail {
BOOST_MPL_HAS_XXX_TRAIT_DEF(type)

template<class T, class Enabler = void>
struct has_range_iterator_impl
    : boost::mpl::false_
{
};

template<class T>
struct has_range_iterator_impl<
    T,
    BOOST_DEDUCED_TYPENAME ::boost::enable_if<
    BOOST_DEDUCED_TYPENAME mpl::eval_if<is_const<T>,
    has_type<boost::range_const_iterator<
    BOOST_DEDUCED_TYPENAME remove_const<T>::type> >,
    has_type<boost::range_mutable_iterator<T> >
    >::type
    >::type
    >
    : boost::mpl::true_
{
};

template<class T, class Enabler = void>
struct has_range_const_iterator_impl
    : boost::mpl::false_
{
};

template<class T>
struct has_range_const_iterator_impl<
    T,
    BOOST_DEDUCED_TYPENAME ::boost::enable_if<
    has_type<boost::range_const_iterator<T> >
    >::type
    >
    : boost::mpl::true_
{
};

} // namespace range_detail

template<class T>
struct has_range_iterator
    : range_detail::has_range_iterator_impl<
      BOOST_DEDUCED_TYPENAME remove_reference<T>::type>
{};

template<class T>
struct has_range_const_iterator
    : range_detail::has_range_const_iterator_impl<
      BOOST_DEDUCED_TYPENAME remove_reference<T>::type>
{};
} // namespace boost

#endif // include guard
