xref: /llvm-project/libcxx/include/__cxx03/__algorithm/unique.h (revision ce7771902dc50d900de639d499a60486b83f70e0)
1e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===//
2e78f53d1SNikolas Klauser //
3e78f53d1SNikolas Klauser // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4e78f53d1SNikolas Klauser // See https://llvm.org/LICENSE.txt for license information.
5e78f53d1SNikolas Klauser // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6e78f53d1SNikolas Klauser //
7e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===//
8e78f53d1SNikolas Klauser 
9*ce777190SNikolas Klauser #ifndef _LIBCPP___CXX03___ALGORITHM_UNIQUE_H
10*ce777190SNikolas Klauser #define _LIBCPP___CXX03___ALGORITHM_UNIQUE_H
11e78f53d1SNikolas Klauser 
1273fbae83SNikolas Klauser #include <__cxx03/__algorithm/adjacent_find.h>
1373fbae83SNikolas Klauser #include <__cxx03/__algorithm/comp.h>
1473fbae83SNikolas Klauser #include <__cxx03/__algorithm/iterator_operations.h>
1573fbae83SNikolas Klauser #include <__cxx03/__config>
1673fbae83SNikolas Klauser #include <__cxx03/__iterator/iterator_traits.h>
1773fbae83SNikolas Klauser #include <__cxx03/__utility/move.h>
1873fbae83SNikolas Klauser #include <__cxx03/__utility/pair.h>
19e78f53d1SNikolas Klauser 
20e78f53d1SNikolas Klauser #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
21e78f53d1SNikolas Klauser #  pragma GCC system_header
22e78f53d1SNikolas Klauser #endif
23e78f53d1SNikolas Klauser 
24e78f53d1SNikolas Klauser _LIBCPP_PUSH_MACROS
2573fbae83SNikolas Klauser #include <__cxx03/__undef_macros>
26e78f53d1SNikolas Klauser 
27e78f53d1SNikolas Klauser _LIBCPP_BEGIN_NAMESPACE_STD
28e78f53d1SNikolas Klauser 
29e78f53d1SNikolas Klauser // unique
30e78f53d1SNikolas Klauser 
31e78f53d1SNikolas Klauser template <class _AlgPolicy, class _Iter, class _Sent, class _BinaryPredicate>
32e78f53d1SNikolas Klauser _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 std::pair<_Iter, _Iter>
33e78f53d1SNikolas Klauser __unique(_Iter __first, _Sent __last, _BinaryPredicate&& __pred) {
34e78f53d1SNikolas Klauser   __first = std::__adjacent_find(__first, __last, __pred);
35e78f53d1SNikolas Klauser   if (__first != __last) {
36e78f53d1SNikolas Klauser     // ...  a  a  ?  ...
37e78f53d1SNikolas Klauser     //      f     i
38e78f53d1SNikolas Klauser     _Iter __i = __first;
39e78f53d1SNikolas Klauser     for (++__i; ++__i != __last;)
40e78f53d1SNikolas Klauser       if (!__pred(*__first, *__i))
41e78f53d1SNikolas Klauser         *++__first = _IterOps<_AlgPolicy>::__iter_move(__i);
42e78f53d1SNikolas Klauser     ++__first;
43e78f53d1SNikolas Klauser     return std::pair<_Iter, _Iter>(std::move(__first), std::move(__i));
44e78f53d1SNikolas Klauser   }
45e78f53d1SNikolas Klauser   return std::pair<_Iter, _Iter>(__first, __first);
46e78f53d1SNikolas Klauser }
47e78f53d1SNikolas Klauser 
48e78f53d1SNikolas Klauser template <class _ForwardIterator, class _BinaryPredicate>
49e78f53d1SNikolas Klauser _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
50e78f53d1SNikolas Klauser unique(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred) {
51e78f53d1SNikolas Klauser   return std::__unique<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __pred).first;
52e78f53d1SNikolas Klauser }
53e78f53d1SNikolas Klauser 
54e78f53d1SNikolas Klauser template <class _ForwardIterator>
55e78f53d1SNikolas Klauser _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
56e78f53d1SNikolas Klauser unique(_ForwardIterator __first, _ForwardIterator __last) {
57e78f53d1SNikolas Klauser   return std::unique(__first, __last, __equal_to());
58e78f53d1SNikolas Klauser }
59e78f53d1SNikolas Klauser 
60e78f53d1SNikolas Klauser _LIBCPP_END_NAMESPACE_STD
61e78f53d1SNikolas Klauser 
62e78f53d1SNikolas Klauser _LIBCPP_POP_MACROS
63e78f53d1SNikolas Klauser 
64*ce777190SNikolas Klauser #endif // _LIBCPP___CXX03___ALGORITHM_UNIQUE_H
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