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)
7 // For more information, see http://www.boost.org/libs/range/
9 #ifndef BOOST_RANGE_DETAIL_RANGE_RETURN_HPP_INCLUDED
10 #define BOOST_RANGE_DETAIL_RANGE_RETURN_HPP_INCLUDED
12 #include <boost/range/begin.hpp>
13 #include <boost/range/end.hpp>
14 #include <boost/range/iterator_range.hpp>
15 #include <boost/next_prior.hpp>
19 enum range_return_value
21 // (*) indicates the most common values
22 return_found, // only the found resulting iterator (*)
23 return_next, // next(found) iterator
24 return_prior, // prior(found) iterator
25 return_begin_found, // [begin, found) range (*)
26 return_begin_next, // [begin, next(found)) range
27 return_begin_prior, // [begin, prior(found)) range
28 return_found_end, // [found, end) range (*)
29 return_next_end, // [next(found), end) range
30 return_prior_end, // [prior(found), end) range
31 return_begin_end // [begin, end) range
34 template< class SinglePassRange, range_return_value >
37 typedef boost::iterator_range<
38 BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type;
40 static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found,
43 return type(found, boost::end(rng));
47 template< class SinglePassRange >
48 struct range_return< SinglePassRange, return_found >
50 typedef BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type type;
52 static type pack(type found, SinglePassRange&)
58 template< class SinglePassRange >
59 struct range_return< SinglePassRange, return_next >
61 typedef BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type type;
63 static type pack(type found, SinglePassRange& rng)
65 return found == boost::end(rng)
71 template< class BidirectionalRange >
72 struct range_return< BidirectionalRange, return_prior >
74 typedef BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type type;
76 static type pack(type found, BidirectionalRange& rng)
78 return found == boost::begin(rng)
80 : boost::prior(found);
84 template< class SinglePassRange >
85 struct range_return< SinglePassRange, return_begin_found >
87 typedef boost::iterator_range<
88 BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type;
90 static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found,
93 return type(boost::begin(rng), found);
97 template< class SinglePassRange >
98 struct range_return< SinglePassRange, return_begin_next >
100 typedef boost::iterator_range<
101 BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type;
103 static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found,
104 SinglePassRange& rng)
106 return type( boost::begin(rng),
107 found == boost::end(rng) ? found : boost::next(found) );
111 template< class BidirectionalRange >
112 struct range_return< BidirectionalRange, return_begin_prior >
114 typedef boost::iterator_range<
115 BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type > type;
117 static type pack(BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type found,
118 BidirectionalRange& rng)
120 return type( boost::begin(rng),
121 found == boost::begin(rng) ? found : boost::prior(found) );
125 template< class SinglePassRange >
126 struct range_return< SinglePassRange, return_found_end >
128 typedef boost::iterator_range<
129 BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type;
131 static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found,
132 SinglePassRange& rng)
134 return type(found, boost::end(rng));
138 template< class SinglePassRange >
139 struct range_return< SinglePassRange, return_next_end >
141 typedef boost::iterator_range<
142 BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type;
144 static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type found,
145 SinglePassRange& rng)
147 return type( found == boost::end(rng) ? found : boost::next(found),
152 template< class BidirectionalRange >
153 struct range_return< BidirectionalRange, return_prior_end >
155 typedef boost::iterator_range<
156 BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type > type;
158 static type pack(BOOST_DEDUCED_TYPENAME range_iterator<BidirectionalRange>::type found,
159 BidirectionalRange& rng)
161 return type( found == boost::begin(rng) ? found : boost::prior(found),
166 template< class SinglePassRange >
167 struct range_return< SinglePassRange, return_begin_end >
169 typedef boost::iterator_range<
170 BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type > type;
172 static type pack(BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type,
173 SinglePassRange& rng)
175 return type(boost::begin(rng), boost::end(rng));
181 #endif // include guard