fusion/include/boost/fusion/adapted/class/extension.hpp

/*=============================================================================
    Copyright (c) 2001-2009 Joel de Guzman
    Copyright (c) 2005-2006 Dan Marsden

    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_CLASS_EXTENSION_OCTOBER_4_2009_839PM)
#define FUSION_CLASS_EXTENSION_OCTOBER_4_2009_839PM

#include <boost/type_traits/add_const.hpp>

namespace boost { namespace fusion
{
    struct fusion_sequence_tag;

    namespace extension
    {
        template <typename Class, int N>
        struct class_member;

        template <typename Class>
        struct class_size;

        template <typename Class, int N>
        struct class_member<Class const, N> : class_member<Class, N> {};

        template <typename Class>
        struct class_size<Class const>
            : class_size<Class>
        {};

        struct no_such_member;

        template<typename Class, typename Key>
        struct class_assoc_member
        {
            typedef no_such_member type;
        };

        template<typename Class, typename Key>
        struct class_assoc_member<Class const, Key>
        {
            typedef typename
                add_const<typename class_assoc_member<Class, Key>::type>::type
            type;

            static type&
            call(Class const& class_)
            {
                return class_assoc_member<Class, Key>::call(
                    const_cast<Class&>(class_));
            }
        };

    }
}}

#endif