1/*=============================================================================
2 Copyright (c) 2001-2011 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_CATEGORY_OF_07202005_0308)
8#define FUSION_CATEGORY_OF_07202005_0308
9
10#include <boost/fusion/support/config.hpp>
11#include <boost/fusion/support/detail/category_of.hpp>
12#include <boost/fusion/support/tag_of.hpp>
13#include <boost/type_traits/is_base_of.hpp>
14
15namespace boost { namespace fusion
16{
17 // Special tags:
18 struct boost_tuple_tag; // boost::tuples::tuple tag
19 struct boost_array_tag; // boost::array tag
20 struct mpl_sequence_tag; // mpl sequence tag
21 struct std_pair_tag; // std::pair tag
22
23 struct incrementable_traversal_tag {};
24
25 struct single_pass_traversal_tag
26 : incrementable_traversal_tag {};
27
28 struct forward_traversal_tag
29 : single_pass_traversal_tag {};
30
31 struct bidirectional_traversal_tag
32 : forward_traversal_tag {};
33
34 struct random_access_traversal_tag
35 : bidirectional_traversal_tag {};
36
37 struct associative_tag {};
38
39 struct unbounded_tag {};
40
41 namespace extension
42 {
43 template<typename Tag>
44 struct category_of_impl
45 {
46 template<typename T>
47 struct apply : detail::fusion_category_of<T> {};
48 };
49
50 template <>
51 struct category_of_impl<boost_tuple_tag>;
52
53 template <>
54 struct category_of_impl<boost_array_tag>;
55
56 template <>
57 struct category_of_impl<mpl_sequence_tag>;
58
59 template <>
60 struct category_of_impl<std_pair_tag>;
61 }
62
63 namespace traits
64 {
65 template <typename T>
66 struct category_of
67 : extension::category_of_impl<typename fusion::detail::tag_of<T>::type>::
68 template apply<T>
69 {};
70
71 template <typename T>
72 struct is_associative
73 : is_base_of<
74 associative_tag
75 , typename category_of<T>::type>
76 {};
77
78 template <typename T>
79 struct is_incrementable
80 : is_base_of<
81 incrementable_traversal_tag
82 , typename category_of<T>::type>
83 {};
84
85 template <typename T>
86 struct is_single_pass
87 : is_base_of<
88 single_pass_traversal_tag
89 , typename category_of<T>::type>
90 {};
91
92 template <typename T>
93 struct is_forward
94 : is_base_of<
95 forward_traversal_tag
96 , typename category_of<T>::type>
97 {};
98
99 template <typename T>
100 struct is_bidirectional
101 : is_base_of<
102 bidirectional_traversal_tag
103 , typename category_of<T>::type>
104 {};
105
106 template <typename T>
107 struct is_random_access
108 : is_base_of<
109 random_access_traversal_tag
110 , typename category_of<T>::type>
111 {};
112
113 template <typename T>
114 struct is_unbounded
115 : is_base_of<
116 unbounded_tag
117 , typename category_of<T>::type>
118 {};
119 }
120}}
121
122#endif
123

source code of boost/boost/fusion/support/category_of.hpp