1 /*=============================================================================
2     Copyright (c) 2001-2006 Joel de Guzman
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(FUSION_FIND_05052005_1107)
8 #define FUSION_FIND_05052005_1107
9 
10 #include <boost/fusion/algorithm/query/detail/find_if.hpp>
11 #include <boost/fusion/sequence/intrinsic/begin.hpp>
12 #include <boost/fusion/sequence/intrinsic/end.hpp>
13 #include <boost/fusion/iterator/key_of.hpp>
14 #include <boost/fusion/iterator/value_of.hpp>
15 #include <boost/fusion/support/category_of.hpp>
16 #include <boost/mpl/if.hpp>
17 #include <boost/type_traits/is_same.hpp>
18 #include <boost/type_traits/is_const.hpp>
19 #include <boost/utility/enable_if.hpp>
20 
21 namespace boost { namespace fusion
22 {
23     namespace result_of
24     {
25         template <
26             typename Sequence
27           , typename T
28         >
29         struct find
30         {
31             typedef
32                 detail::static_find_if<
33                     typename result_of::begin<Sequence>::type
34                   , typename result_of::end<Sequence>::type
35                   , is_same<
36                         typename mpl::if_<
37                             traits::is_associative<Sequence>
38                           , key_of<mpl::_1>
39                           , value_of<mpl::_1>
40                         >::type
41                       , T
42                     >
43                 >
44             filter;
45 
46             typedef typename filter::type type;
47         };
48     }
49 
50     template <typename T, typename Sequence>
51     inline typename
52         lazy_disable_if<
53             is_const<Sequence>
54           , result_of::find<Sequence, T>
55         >::type const
find(Sequence & seq)56     find(Sequence& seq)
57     {
58         typedef typename result_of::find<Sequence, T>::filter filter;
59         return filter::call(fusion::begin(seq));
60     }
61 
62     template <typename T, typename Sequence>
63     inline typename result_of::find<Sequence const, T>::type const
find(Sequence const & seq)64     find(Sequence const& seq)
65     {
66         typedef typename result_of::find<Sequence const, T>::filter filter;
67         return filter::call(fusion::begin(seq));
68     }
69 }}
70 
71 #endif
72 
73