1 /*=============================================================================
2 Copyright (c) 2001-2011 Joel de Guzman
4 Distributed under the Boost Software License, Version 1.0. (See accompanying
5 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6 ==============================================================================*/
7 #if !defined(FUSION_TAG_OF_09232005_0845)
8 #define FUSION_TAG_OF_09232005_0845
10 #include <boost/utility/enable_if.hpp>
11 #include <boost/type_traits/remove_const.hpp>
12 #include <boost/fusion/support/tag_of_fwd.hpp>
13 #include <boost/fusion/support/detail/is_mpl_sequence.hpp>
14 #include <boost/mpl/has_xxx.hpp>
15 #include <boost/mpl/identity.hpp>
16 #include <boost/mpl/assert.hpp>
17 #include <boost/mpl/bool.hpp>
18 #include <boost/mpl/if.hpp>
19 #include <boost/config/no_tr1/utility.hpp>
23 template <typename T, std::size_t N>
24 class array; // forward
31 class T0, class T1, class T2, class T3, class T4,
32 class T5, class T6, class T7, class T8, class T9
36 template <class Head, class Tail>
41 namespace boost { namespace fusion
43 struct non_fusion_tag;
44 struct mpl_sequence_tag;
48 BOOST_MPL_HAS_XXX_TRAIT_DEF(fusion_tag)
50 template <typename Sequence, typename Active>
52 : mpl::if_<fusion::detail::is_mpl_sequence<Sequence>,
53 mpl::identity<mpl_sequence_tag>,
54 mpl::identity<non_fusion_tag> >::type
57 template <typename Sequence>
60 , typename boost::enable_if<detail::has_fusion_tag<Sequence> >::type>
62 typedef typename Sequence::fusion_tag type;
68 template <typename Sequence, typename Active>
70 : boost::fusion::detail::tag_of_impl<Sequence, Active>
78 : traits::tag_of<typename remove_const<T>::type>