| /*============================================================================= |
| 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_NEXT_IMPL_06052005_0900) |
| #define FUSION_NEXT_IMPL_06052005_0900 |
| |
| #include <boost/fusion/algorithm/query/detail/find_if.hpp> |
| #include <boost/fusion/iterator/value_of.hpp> |
| #include <boost/mpl/eval_if.hpp> |
| #include <boost/mpl/identity.hpp> |
| #include <boost/mpl/lambda.hpp> |
| #include <boost/mpl/quote.hpp> |
| #include <boost/mpl/bind.hpp> |
| #include <boost/mpl/placeholders.hpp> |
| |
| namespace boost { namespace fusion |
| { |
| struct filter_view_iterator_tag; |
| |
| template <typename Category, typename First, typename Last, typename Pred> |
| struct filter_iterator; |
| |
| namespace extension |
| { |
| template <typename Tag> |
| struct next_impl; |
| |
| template <> |
| struct next_impl<filter_view_iterator_tag> |
| { |
| template <typename Iterator> |
| struct apply |
| { |
| typedef typename Iterator::first_type first_type; |
| typedef typename Iterator::last_type last_type; |
| typedef typename Iterator::pred_type pred_type; |
| typedef typename Iterator::category category; |
| |
| typedef typename |
| mpl::eval_if< |
| result_of::equal_to<first_type, last_type> |
| , mpl::identity<last_type> |
| , result_of::next<first_type> |
| >::type |
| next_type; |
| |
| typedef typename |
| detail::static_find_if< |
| next_type |
| , last_type |
| , mpl::bind1< |
| typename mpl::lambda<pred_type>::type |
| , mpl::bind1<mpl::quote1<result_of::value_of>,mpl::_1> |
| > |
| > |
| filter; |
| |
| typedef filter_iterator< |
| category, typename filter::type, last_type, pred_type> |
| type; |
| |
| static type |
| call(Iterator const& i) |
| { |
| return type(filter::call(i.first)); |
| } |
| }; |
| }; |
| } |
| }} |
| |
| #endif |
| |
| |