1 | // Copyright Neil Groves 2009. Use, modification and |
2 | // distribution is subject to the Boost Software License, Version |
3 | // 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
4 | // http://www.boost.org/LICENSE_1_0.txt) |
5 | // |
6 | // |
7 | // For more information, see http://www.boost.org/libs/range/ |
8 | // |
9 | #ifndef BOOST_RANGE_DETAIL_RANGE_RETURN_HPP_INCLUDED |
10 | #define BOOST_RANGE_DETAIL_RANGE_RETURN_HPP_INCLUDED |
11 | |
12 | #include <boost/range/begin.hpp> |
13 | #include <boost/range/end.hpp> |
14 | #include <boost/range/iterator_range.hpp> |
15 | |
16 | namespace boost |
17 | { |
18 | enum range_return_value |
19 | { |
20 | // (*) indicates the most common values |
21 | return_found, // only the found resulting iterator (*) |
22 | return_next, // next(found) iterator |
23 | return_prior, // prior(found) iterator |
24 | return_begin_found, // [begin, found) range (*) |
25 | return_begin_next, // [begin, next(found)) range |
26 | return_begin_prior, // [begin, prior(found)) range |
27 | return_found_end, // [found, end) range (*) |
28 | return_next_end, // [next(found), end) range |
29 | return_prior_end, // [prior(found), end) range |
30 | return_begin_end // [begin, end) range |
31 | }; |
32 | |
33 | template< class SinglePassRange, range_return_value > |
34 | struct range_return |
35 | { |
36 | typedef boost::iterator_range< |
37 | BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type; |
38 | |
39 | static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found, |
40 | SinglePassRange& rng) |
41 | { |
42 | return type(found, boost::end(rng)); |
43 | } |
44 | }; |
45 | |
46 | template< class SinglePassRange > |
47 | struct range_return< SinglePassRange, return_found > |
48 | { |
49 | typedef BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type type; |
50 | |
51 | static type pack(type found, SinglePassRange&) |
52 | { |
53 | return found; |
54 | } |
55 | }; |
56 | |
57 | template< class SinglePassRange > |
58 | struct range_return< SinglePassRange, return_next > |
59 | { |
60 | typedef BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type type; |
61 | |
62 | static type pack(type found, SinglePassRange& rng) |
63 | { |
64 | return found == boost::end(rng) |
65 | ? found |
66 | : boost::next(found); |
67 | } |
68 | }; |
69 | |
70 | template< class BidirectionalRange > |
71 | struct range_return< BidirectionalRange, return_prior > |
72 | { |
73 | typedef BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type type; |
74 | |
75 | static type pack(type found, BidirectionalRange& rng) |
76 | { |
77 | return found == boost::begin(rng) |
78 | ? found |
79 | : boost::prior(found); |
80 | } |
81 | }; |
82 | |
83 | template< class SinglePassRange > |
84 | struct range_return< SinglePassRange, return_begin_found > |
85 | { |
86 | typedef boost::iterator_range< |
87 | BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type; |
88 | |
89 | static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found, |
90 | SinglePassRange& rng) |
91 | { |
92 | return type(boost::begin(rng), found); |
93 | } |
94 | }; |
95 | |
96 | template< class SinglePassRange > |
97 | struct range_return< SinglePassRange, return_begin_next > |
98 | { |
99 | typedef boost::iterator_range< |
100 | BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type; |
101 | |
102 | static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found, |
103 | SinglePassRange& rng) |
104 | { |
105 | return type( boost::begin(rng), |
106 | found == boost::end(rng) ? found : boost::next(found) ); |
107 | } |
108 | }; |
109 | |
110 | template< class BidirectionalRange > |
111 | struct range_return< BidirectionalRange, return_begin_prior > |
112 | { |
113 | typedef boost::iterator_range< |
114 | BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type > type; |
115 | |
116 | static type pack(BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type found, |
117 | BidirectionalRange& rng) |
118 | { |
119 | return type( boost::begin(rng), |
120 | found == boost::begin(rng) ? found : boost::prior(found) ); |
121 | } |
122 | }; |
123 | |
124 | template< class SinglePassRange > |
125 | struct range_return< SinglePassRange, return_found_end > |
126 | { |
127 | typedef boost::iterator_range< |
128 | BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type; |
129 | |
130 | static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found, |
131 | SinglePassRange& rng) |
132 | { |
133 | return type(found, boost::end(rng)); |
134 | } |
135 | }; |
136 | |
137 | template< class SinglePassRange > |
138 | struct range_return< SinglePassRange, return_next_end > |
139 | { |
140 | typedef boost::iterator_range< |
141 | BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type; |
142 | |
143 | static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found, |
144 | SinglePassRange& rng) |
145 | { |
146 | return type( found == boost::end(rng) ? found : boost::next(found), |
147 | boost::end(rng) ); |
148 | } |
149 | }; |
150 | |
151 | template< class BidirectionalRange > |
152 | struct range_return< BidirectionalRange, return_prior_end > |
153 | { |
154 | typedef boost::iterator_range< |
155 | BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type > type; |
156 | |
157 | static type pack(BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type found, |
158 | BidirectionalRange& rng) |
159 | { |
160 | return type( found == boost::begin(rng) ? found : boost::prior(found), |
161 | boost::end(rng) ); |
162 | } |
163 | }; |
164 | |
165 | template< class SinglePassRange > |
166 | struct range_return< SinglePassRange, return_begin_end > |
167 | { |
168 | typedef boost::iterator_range< |
169 | BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type; |
170 | |
171 | static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type, |
172 | SinglePassRange& rng) |
173 | { |
174 | return type(boost::begin(rng), boost::end(rng)); |
175 | } |
176 | }; |
177 | |
178 | } |
179 | |
180 | #endif // include guard |
181 | |