1 | // Boost.Range library |
---|---|
2 | // |
3 | // Copyright Thorsten Ottosen, Neil Groves 2006 - 2008. Use, modification and |
4 | // distribution is subject to the Boost Software License, Version |
5 | // 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
6 | // http://www.boost.org/LICENSE_1_0.txt) |
7 | // |
8 | // For more information, see http://www.boost.org/libs/range/ |
9 | // |
10 | |
11 | #ifndef BOOST_RANGE_ADAPTOR_REVERSED_HPP |
12 | #define BOOST_RANGE_ADAPTOR_REVERSED_HPP |
13 | |
14 | #include <boost/range/iterator_range.hpp> |
15 | #include <boost/range/concepts.hpp> |
16 | #include <boost/iterator/reverse_iterator.hpp> |
17 | |
18 | namespace boost |
19 | { |
20 | namespace range_detail |
21 | { |
22 | template< class R > |
23 | struct reversed_range : |
24 | public boost::iterator_range< |
25 | boost::reverse_iterator< |
26 | BOOST_DEDUCED_TYPENAME range_iterator<R>::type |
27 | > |
28 | > |
29 | { |
30 | private: |
31 | typedef boost::iterator_range< |
32 | boost::reverse_iterator< |
33 | BOOST_DEDUCED_TYPENAME range_iterator<R>::type |
34 | > |
35 | > |
36 | base; |
37 | |
38 | public: |
39 | typedef boost::reverse_iterator<BOOST_DEDUCED_TYPENAME range_iterator<R>::type> iterator; |
40 | |
41 | explicit reversed_range( R& r ) |
42 | : base( iterator(boost::end(r)), iterator(boost::begin(r)) ) |
43 | { } |
44 | }; |
45 | |
46 | struct reverse_forwarder {}; |
47 | |
48 | template< class BidirectionalRange > |
49 | inline reversed_range<BidirectionalRange> |
50 | operator|( BidirectionalRange& r, reverse_forwarder ) |
51 | { |
52 | BOOST_RANGE_CONCEPT_ASSERT(( |
53 | BidirectionalRangeConcept<BidirectionalRange>)); |
54 | |
55 | return reversed_range<BidirectionalRange>( r ); |
56 | } |
57 | |
58 | template< class BidirectionalRange > |
59 | inline reversed_range<const BidirectionalRange> |
60 | operator|( const BidirectionalRange& r, reverse_forwarder ) |
61 | { |
62 | BOOST_RANGE_CONCEPT_ASSERT(( |
63 | BidirectionalRangeConcept<const BidirectionalRange>)); |
64 | |
65 | return reversed_range<const BidirectionalRange>( r ); |
66 | } |
67 | |
68 | } // 'range_detail' |
69 | |
70 | using range_detail::reversed_range; |
71 | |
72 | namespace adaptors |
73 | { |
74 | namespace |
75 | { |
76 | const range_detail::reverse_forwarder reversed = |
77 | range_detail::reverse_forwarder(); |
78 | } |
79 | |
80 | template<class BidirectionalRange> |
81 | inline reversed_range<BidirectionalRange> |
82 | reverse(BidirectionalRange& rng) |
83 | { |
84 | BOOST_RANGE_CONCEPT_ASSERT(( |
85 | BidirectionalRangeConcept<BidirectionalRange>)); |
86 | |
87 | return reversed_range<BidirectionalRange>(rng); |
88 | } |
89 | |
90 | template<class BidirectionalRange> |
91 | inline reversed_range<const BidirectionalRange> |
92 | reverse(const BidirectionalRange& rng) |
93 | { |
94 | BOOST_RANGE_CONCEPT_ASSERT(( |
95 | BidirectionalRangeConcept<const BidirectionalRange>)); |
96 | |
97 | return reversed_range<const BidirectionalRange>(rng); |
98 | } |
99 | } // 'adaptors' |
100 | |
101 | } // 'boost' |
102 | |
103 | #endif |
104 |