boost/range/detail/value_type.hpp

// Boost.Range library
//
//  Copyright Thorsten Ottosen 2003-2004. 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/
//
#ifndef BOOST_RANGE_DETAIL_VALUE_TYPE_HPP
#define BOOST_RANGE_DETAIL_VALUE_TYPE_HPP
#include <boost/range/detail/common.hpp>
#include <boost/range/detail/remove_extent.hpp>
#include <boost/iterator/iterator_traits.hpp>
//////////////////////////////////////////////////////////////////////////////
// missing partial specialization  workaround.
//////////////////////////////////////////////////////////////////////////////
namespace boost 
{
    namespace range_detail 
    {        
        template< typename T >
        struct range_value_type_;
        template<>
        struct range_value_type_<std_container_>
        {
            template< typename C >
            struct pts
            {
                typedef BOOST_RANGE_DEDUCED_TYPENAME C::value_type type;
            };
        };
        template<>
        struct range_value_type_<std_pair_>
        {
            template< typename P >
            struct pts
            {
                typedef BOOST_RANGE_DEDUCED_TYPENAME boost::iterator_value< BOOST_RANGE_DEDUCED_TYPENAME P::first_type >::type type;
            };
        };
        template<>
        struct range_value_type_<array_>
        { 
            template< typename T >
            struct pts
            {
                typedef BOOST_DEDUCED_TYPENAME remove_extent<T>::type type;
            };
        };
        
    } 
    
    template< typename C >
    class range_value
    {
        typedef BOOST_DEDUCED_TYPENAME range_detail::range<C>::type c_type;
    public:
        typedef BOOST_DEDUCED_TYPENAME range_detail::range_value_type_<c_type>::BOOST_NESTED_TEMPLATE pts<C>::type type; 
    };
}
#endif