| /*============================================================================= | |
| Copyright (c) 2001-2006 Joel de Guzman | |
| 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_BEGIN_IMPL_07162005_0115) | |
| #define FUSION_BEGIN_IMPL_07162005_0115 | |
| #include <boost/fusion/iterator/equal_to.hpp> | |
| #include <boost/mpl/if.hpp> | |
| namespace boost { namespace fusion | |
| { | |
| struct joint_view_tag; | |
| template <typename Category, typename First, typename Last, typename Concat> | |
| struct joint_view_iterator; | |
| namespace extension | |
| { | |
| template <typename Tag> | |
| struct begin_impl; | |
| template <> | |
| struct begin_impl<joint_view_tag> | |
| { | |
| template <typename Sequence> | |
| struct apply | |
| { | |
| typedef typename Sequence::first_type first_type; | |
| typedef typename Sequence::last_type last_type; | |
| typedef typename Sequence::concat_type concat_type; | |
| typedef typename Sequence::category category; | |
| typedef result_of::equal_to<first_type, last_type> equal_to; | |
| typedef typename | |
| mpl::if_< | |
| equal_to | |
| , concat_type | |
| , joint_view_iterator<category, first_type, last_type, concat_type> | |
| >::type | |
| type; | |
| static type | |
| call(Sequence& s, mpl::true_) | |
| { | |
| return s.concat(); | |
| } | |
| static type | |
| call(Sequence& s, mpl::false_) | |
| { | |
| return type(s.first(), s.concat()); | |
| } | |
| static type | |
| call(Sequence& s) | |
| { | |
| return call(s, equal_to()); | |
| } | |
| }; | |
| }; | |
| } | |
| }} | |
| #endif |