1[/
2    Copyright 2010 Neil Groves
3    Distributed under the Boost Software License, Version 1.0.
4    (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
5/]
6[section:unique unique]
7
8[heading Prototype]
9
10``
11template<class ForwardRange>
12typename range_return<ForwardRange, return_begin_found>::type
13unique(ForwardRange& rng);
14
15template<class ForwardRange>
16typename range_return<const ForwardRange, return_begin_found>::type
17unique(const ForwardRange& rng);
18
19template<class ForwardRange, class BinaryPredicate>
20typename range_return<ForwardRange, return_begin_found>::type
21unique(ForwardRange& rng, BinaryPredicate pred);
22
23template<class ForwardRange, class BinaryPredicate>
24typename range_return<const ForwardRange, return_begin_found>::type
25unique(const ForwardRange& rng, BinaryPredicate pred);
26
27template<range_return_value re, class ForwardRange>
28typename range_return<ForwardRange, re>::type
29unique(ForwardRange& rng);
30
31template<range_return_value re, class ForwardRange>
32typename range_return<const ForwardRange, re>::type
33unique(const ForwardRange& rng);
34
35template<range_return_value re, class ForwardRange, class BinaryPredicate>
36typename range_return<ForwardRange, re>::type
37unique(ForwardRange& rng, BinaryPredicate pred);
38
39template<range_return_value re, class ForwardRange, class BinaryPredicate>
40typename range_return<const ForwardRange, re>::type
41unique(const ForwardRange& rng, BinaryPredicate pred);
42``
43
44[heading Description]
45
46`unique` removes all but the first element of each sequence of duplicate encountered in `rng`.
47
48Elements in the range `[new_last, end(rng))` are dereferenceable but undefined.
49
50Equality is determined by the predicate if one is supplied, or by `operator==()` for `ForwardRange`'s value type.
51
52[heading Definition]
53
54Defined in the header file `boost/range/algorithm/unique.hpp`
55
56[heading Requirements]
57
58[*For the non-predicate versions of unique:]
59
60* `ForwardRange` is a model of the __forward_range__ Concept.
61* `ForwardRange` is mutable.
62* `ForwardRange`'s value type is a model of the `EqualityComparableConcept`.
63
64[*For the predicate versions of unique:]
65
66* `ForwardRange` is a model of the __forward_range__ Concept.
67* `ForwardRange` is mutable.
68* `BinaryPredicate` is a model of the `BinaryPredicateConcept`.
69* `ForwardRange`'s value type is convertible to `BinaryPredicate`'s first argument type and to `BinaryPredicate`'s second argument type.
70
71[heading Complexity]
72
73Linear. `O(N)` where `N` is `distance(rng)`. Exactly `distance(rng)` comparisons are performed.
74
75[endsect]
76
77
78