]>
Commit | Line | Data |
---|---|---|
7c673cae FG |
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 | // $Id$ | |
14 | // $Date$ | |
15 | // $Revision$ | |
16 | ||
17 | #include <boost/mpl/eval_if.hpp> | |
18 | #include <boost/mpl/void.hpp> | |
19 | #include <boost/mpl/aux_/has_tag.hpp> | |
20 | #include <boost/mpl/aux_/config/eti.hpp> | |
21 | ||
22 | namespace boost { 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 |