1 | |
2 | #ifndef BOOST_MPL_AUX_FILTER_ITER_HPP_INCLUDED |
3 | #define BOOST_MPL_AUX_FILTER_ITER_HPP_INCLUDED |
4 | |
5 | // Copyright Aleksey Gurtovoy 2000-2004 |
6 | // |
7 | // Distributed under the Boost Software License, Version 1.0. |
8 | // (See accompanying file LICENSE_1_0.txt or copy at |
9 | // http://www.boost.org/LICENSE_1_0.txt) |
10 | // |
11 | // See http://www.boost.org/libs/mpl for documentation. |
12 | |
13 | // $Id$ |
14 | // $Date$ |
15 | // $Revision$ |
16 | |
17 | #include <boost/mpl/find_if.hpp> |
18 | #include <boost/mpl/iterator_range.hpp> |
19 | #include <boost/mpl/iterator_tags.hpp> |
20 | #include <boost/mpl/deref.hpp> |
21 | #include <boost/mpl/aux_/lambda_spec.hpp> |
22 | #include <boost/mpl/aux_/config/ctps.hpp> |
23 | #include <boost/type_traits/is_same.hpp> |
24 | |
25 | namespace boost { namespace mpl { |
26 | |
27 | namespace aux { |
28 | |
29 | template< |
30 | typename Iterator |
31 | , typename LastIterator |
32 | , typename Predicate |
33 | > |
34 | struct filter_iter; |
35 | |
36 | template< |
37 | typename Iterator |
38 | , typename LastIterator |
39 | , typename Predicate |
40 | > |
41 | struct next_filter_iter |
42 | { |
43 | typedef typename find_if< |
44 | iterator_range<Iterator,LastIterator> |
45 | , Predicate |
46 | >::type base_iter_; |
47 | |
48 | typedef filter_iter<base_iter_,LastIterator,Predicate> type; |
49 | }; |
50 | |
51 | #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) |
52 | |
53 | template< |
54 | typename Iterator |
55 | , typename LastIterator |
56 | , typename Predicate |
57 | > |
58 | struct filter_iter |
59 | { |
60 | typedef Iterator base; |
61 | typedef forward_iterator_tag category; |
62 | typedef typename aux::next_filter_iter< |
63 | typename mpl::next<base>::type |
64 | , LastIterator |
65 | , Predicate |
66 | >::type next; |
67 | |
68 | typedef typename deref<base>::type type; |
69 | }; |
70 | |
71 | template< |
72 | typename LastIterator |
73 | , typename Predicate |
74 | > |
75 | struct filter_iter< LastIterator,LastIterator,Predicate > |
76 | { |
77 | typedef LastIterator base; |
78 | typedef forward_iterator_tag category; |
79 | }; |
80 | |
81 | #else |
82 | |
83 | template< bool > |
84 | struct filter_iter_impl |
85 | { |
86 | template< |
87 | typename Iterator |
88 | , typename LastIterator |
89 | , typename Predicate |
90 | > |
91 | struct result_ |
92 | { |
93 | typedef Iterator base; |
94 | typedef forward_iterator_tag category; |
95 | typedef typename next_filter_iter< |
96 | typename mpl::next<Iterator>::type |
97 | , LastIterator |
98 | , Predicate |
99 | >::type next; |
100 | |
101 | typedef typename deref<base>::type type; |
102 | }; |
103 | }; |
104 | |
105 | template<> |
106 | struct filter_iter_impl< true > |
107 | { |
108 | template< |
109 | typename Iterator |
110 | , typename LastIterator |
111 | , typename Predicate |
112 | > |
113 | struct result_ |
114 | { |
115 | typedef Iterator base; |
116 | typedef forward_iterator_tag category; |
117 | }; |
118 | }; |
119 | |
120 | template< |
121 | typename Iterator |
122 | , typename LastIterator |
123 | , typename Predicate |
124 | > |
125 | struct filter_iter |
126 | : filter_iter_impl< |
127 | ::boost::is_same<Iterator,LastIterator>::value |
128 | >::template result_< Iterator,LastIterator,Predicate > |
129 | { |
130 | }; |
131 | |
132 | #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION |
133 | |
134 | } // namespace aux |
135 | |
136 | BOOST_MPL_AUX_PASS_THROUGH_LAMBDA_SPEC(3, aux::filter_iter) |
137 | |
138 | }} |
139 | |
140 | #endif // BOOST_MPL_AUX_FILTER_ITER_HPP_INCLUDED |
141 | |