| /*============================================================================= |
| Copyright (c) 2001-2007 Joel de Guzman |
| Copyright (c) 2005-2007 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(BOOST_FUSION_HAS_KEY_IMPL_20070508_2231) |
| #define BOOST_FUSION_HAS_KEY_IMPL_20070508_2231 |
| |
| #include <boost/type_traits/is_same.hpp> |
| #include <boost/mpl/not.hpp> |
| |
| namespace boost { namespace fusion { |
| |
| struct struct_tag; |
| |
| namespace extension |
| { |
| struct no_such_member; |
| |
| template<typename T> |
| struct has_key_impl; |
| |
| template<typename Struct, typename Key> |
| struct struct_assoc_member; |
| |
| template<> |
| struct has_key_impl<struct_tag> |
| { |
| template<typename Sequence, typename Key> |
| struct apply |
| : mpl::not_<is_same<no_such_member, typename struct_assoc_member<Sequence, Key>::type> > |
| { |
| }; |
| }; |
| } |
| }} |
| |
| #endif |