1 // Boost.Range library 2 // 3 // Copyright Thorsten Ottosen 2003-2004. Use, modification and 4 // distribution is subject to the Boost Software License, Version 5 // 1.0. (See accompanying file LICENSE_1_0.txt or copy at 6 // http://www.boost.org/LICENSE_1_0.txt) 7 // 8 // For more information, see http://www.boost.org/libs/range/ 9 // 10 11 #ifndef BOOST_RANGE_DIFFERENCE_TYPE_HPP 12 #define BOOST_RANGE_DIFFERENCE_TYPE_HPP 13 14 #if defined(_MSC_VER) 15 # pragma once 16 #endif 17 18 #include <boost/mpl/and.hpp> 19 #include <boost/range/config.hpp> 20 #include <boost/range/iterator.hpp> 21 #include <boost/range/has_range_iterator.hpp> 22 #include <boost/iterator/iterator_traits.hpp> 23 #include <boost/type_traits/remove_reference.hpp> 24 25 namespace boost 26 { 27 namespace range_detail 28 { 29 template< class T, bool B = has_type<range_iterator<T> >::value > 30 struct range_difference 31 { }; 32 33 template< class T > 34 struct range_difference<T, true> 35 : iterator_difference< 36 BOOST_DEDUCED_TYPENAME range_iterator<T>::type 37 > 38 { }; 39 } 40 41 template< class T > 42 struct range_difference 43 : range_detail::range_difference<BOOST_DEDUCED_TYPENAME remove_reference<T>::type> 44 { }; 45 } 46 47 #endif 48