Jeff Thompson | a28eed8 | 2013-08-22 16:21:10 -0700 | [diff] [blame] | 1 | |
| 2 | #ifndef BOOST_MPL_TAG_HPP_INCLUDED |
| 3 | #define BOOST_MPL_TAG_HPP_INCLUDED |
| 4 | |
| 5 | // Copyright Aleksey Gurtovoy 2004 |
| 6 | // |
| 7 | // Distributed under the Boost Software License, Version 1.0. |
| 8 | // (See accompanying file LICENSE_1_0.txt or copy at |
| 9 | // http://www.boost.org/LICENSE_1_0.txt) |
| 10 | // |
| 11 | // See http://www.boost.org/libs/mpl for documentation. |
| 12 | |
| 13 | // $Id: tag.hpp 49267 2008-10-11 06:19:02Z agurtovoy $ |
| 14 | // $Date: 2008-10-10 23:19:02 -0700 (Fri, 10 Oct 2008) $ |
| 15 | // $Revision: 49267 $ |
| 16 | |
| 17 | #include <ndnboost/mpl/eval_if.hpp> |
| 18 | #include <ndnboost/mpl/void.hpp> |
| 19 | #include <ndnboost/mpl/aux_/has_tag.hpp> |
| 20 | #include <ndnboost/mpl/aux_/config/eti.hpp> |
| 21 | |
| 22 | namespace ndnboost { namespace mpl { |
| 23 | |
| 24 | namespace aux { |
| 25 | template< typename T > struct tag_impl |
| 26 | { |
| 27 | typedef typename T::tag type; |
| 28 | }; |
| 29 | } |
| 30 | |
| 31 | template< typename T, typename Default = void_ > struct tag |
| 32 | #if !defined(BOOST_MPL_CFG_MSVC_ETI_BUG) |
| 33 | : if_< |
| 34 | aux::has_tag<T> |
| 35 | , aux::tag_impl<T> |
| 36 | , Default |
| 37 | >::type |
| 38 | { |
| 39 | #else |
| 40 | { |
| 41 | typedef typename eval_if< |
| 42 | aux::has_tag<T> |
| 43 | , aux::tag_impl<T> |
| 44 | , Default |
| 45 | >::type type; |
| 46 | |
| 47 | #endif |
| 48 | }; |
| 49 | |
| 50 | }} |
| 51 | |
| 52 | #endif // BOOST_MPL_TAG_HPP_INCLUDED |