xref: /freebsd-src/contrib/llvm-project/libcxx/include/__algorithm/unique.h (revision fe6060f10f634930ff71b7c50291ddc610da2475)
1*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
2*fe6060f1SDimitry Andric //
3*fe6060f1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*fe6060f1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
5*fe6060f1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*fe6060f1SDimitry Andric //
7*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
8*fe6060f1SDimitry Andric 
9*fe6060f1SDimitry Andric #ifndef _LIBCPP___ALGORITHM_UNIQUE_H
10*fe6060f1SDimitry Andric #define _LIBCPP___ALGORITHM_UNIQUE_H
11*fe6060f1SDimitry Andric 
12*fe6060f1SDimitry Andric #include <__config>
13*fe6060f1SDimitry Andric #include <__algorithm/comp.h>
14*fe6060f1SDimitry Andric #include <__algorithm/adjacent_find.h>
15*fe6060f1SDimitry Andric #include <__iterator/iterator_traits.h>
16*fe6060f1SDimitry Andric #include <__utility/move.h>
17*fe6060f1SDimitry Andric #include <type_traits>
18*fe6060f1SDimitry Andric 
19*fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
20*fe6060f1SDimitry Andric #pragma GCC system_header
21*fe6060f1SDimitry Andric #endif
22*fe6060f1SDimitry Andric 
23*fe6060f1SDimitry Andric _LIBCPP_PUSH_MACROS
24*fe6060f1SDimitry Andric #include <__undef_macros>
25*fe6060f1SDimitry Andric 
26*fe6060f1SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
27*fe6060f1SDimitry Andric 
28*fe6060f1SDimitry Andric // unique
29*fe6060f1SDimitry Andric 
30*fe6060f1SDimitry Andric template <class _ForwardIterator, class _BinaryPredicate>
31*fe6060f1SDimitry Andric _LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
32*fe6060f1SDimitry Andric unique(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
33*fe6060f1SDimitry Andric {
34*fe6060f1SDimitry Andric     __first = _VSTD::adjacent_find<_ForwardIterator, typename add_lvalue_reference<_BinaryPredicate>::type>
35*fe6060f1SDimitry Andric                                  (__first, __last, __pred);
36*fe6060f1SDimitry Andric     if (__first != __last)
37*fe6060f1SDimitry Andric     {
38*fe6060f1SDimitry Andric         // ...  a  a  ?  ...
39*fe6060f1SDimitry Andric         //      f     i
40*fe6060f1SDimitry Andric         _ForwardIterator __i = __first;
41*fe6060f1SDimitry Andric         for (++__i; ++__i != __last;)
42*fe6060f1SDimitry Andric             if (!__pred(*__first, *__i))
43*fe6060f1SDimitry Andric                 *++__first = _VSTD::move(*__i);
44*fe6060f1SDimitry Andric         ++__first;
45*fe6060f1SDimitry Andric     }
46*fe6060f1SDimitry Andric     return __first;
47*fe6060f1SDimitry Andric }
48*fe6060f1SDimitry Andric 
49*fe6060f1SDimitry Andric template <class _ForwardIterator>
50*fe6060f1SDimitry Andric _LIBCPP_NODISCARD_EXT inline
51*fe6060f1SDimitry Andric _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
52*fe6060f1SDimitry Andric _ForwardIterator
53*fe6060f1SDimitry Andric unique(_ForwardIterator __first, _ForwardIterator __last)
54*fe6060f1SDimitry Andric {
55*fe6060f1SDimitry Andric     typedef typename iterator_traits<_ForwardIterator>::value_type __v;
56*fe6060f1SDimitry Andric     return _VSTD::unique(__first, __last, __equal_to<__v>());
57*fe6060f1SDimitry Andric }
58*fe6060f1SDimitry Andric 
59*fe6060f1SDimitry Andric _LIBCPP_END_NAMESPACE_STD
60*fe6060f1SDimitry Andric 
61*fe6060f1SDimitry Andric _LIBCPP_POP_MACROS
62*fe6060f1SDimitry Andric 
63*fe6060f1SDimitry Andric #endif // _LIBCPP___ALGORITHM_UNIQUE_H
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