1 /*============================================================================= 2 Copyright (c) 2011 Eric Niebler 3 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(BOOST_FUSION_SEGMENTED_FIND_IF_HPP_INCLUDED) 8 #define BOOST_FUSION_SEGMENTED_FIND_IF_HPP_INCLUDED 9 10 #include <boost/fusion/support/config.hpp> 11 #include <boost/mpl/eval_if.hpp> 12 #include <boost/mpl/identity.hpp> 13 #include <boost/fusion/algorithm/query/find_if_fwd.hpp> 14 #include <boost/fusion/iterator/equal_to.hpp> 15 #include <boost/fusion/sequence/intrinsic/end.hpp> 16 #include <boost/fusion/support/segmented_fold_until.hpp> 17 18 namespace boost { namespace fusion { namespace detail 19 { 20 template <typename Pred> 21 struct segmented_find_if_fun 22 { 23 template <typename Sequence, typename State, typename Context> 24 struct apply 25 { 26 typedef 27 typename result_of::find_if<Sequence, Pred>::type 28 iterator_type; 29 30 typedef 31 typename result_of::equal_to< 32 iterator_type 33 , typename result_of::end<Sequence>::type 34 >::type 35 continue_type; 36 37 typedef 38 typename mpl::eval_if< 39 continue_type 40 , mpl::identity<State> 41 , result_of::make_segmented_iterator< 42 iterator_type 43 , Context 44 > 45 >::type 46 type; 47 48 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED callboost::fusion::detail::segmented_find_if_fun::apply49 static type call(Sequence& seq, State const&state, Context const& context, segmented_find_if_fun) 50 { 51 return call_impl(seq, state, context, continue_type()); 52 } 53 54 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED call_implboost::fusion::detail::segmented_find_if_fun::apply55 static type call_impl(Sequence&, State const&state, Context const&, mpl::true_) 56 { 57 return state; 58 } 59 60 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED call_implboost::fusion::detail::segmented_find_if_fun::apply61 static type call_impl(Sequence& seq, State const&, Context const& context, mpl::false_) 62 { 63 return fusion::make_segmented_iterator(fusion::find_if<Pred>(seq), context); 64 } 65 }; 66 }; 67 68 template <typename Sequence, typename Pred> 69 struct result_of_segmented_find_if 70 { 71 struct filter 72 { 73 typedef 74 typename result_of::segmented_fold_until< 75 Sequence 76 , typename result_of::end<Sequence>::type 77 , segmented_find_if_fun<Pred> 78 >::type 79 type; 80 81 BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED callboost::fusion::detail::result_of_segmented_find_if::filter82 static type call(Sequence& seq) 83 { 84 return fusion::segmented_fold_until( 85 seq 86 , fusion::end(seq) 87 , segmented_find_if_fun<Pred>()); 88 } 89 }; 90 91 typedef typename filter::type type; 92 }; 93 }}} 94 95 #endif 96