1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef _LIBCPP___ALGORITHM_UNIQUE_COPY_H
10 #define _LIBCPP___ALGORITHM_UNIQUE_COPY_H
11 
12 #include <__config>
13 #include <__algorithm/comp.h>
14 #include <__iterator/iterator_traits.h>
15 #include <utility>
16 #include <type_traits>
17 
18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19 #pragma GCC system_header
20 #endif
21 
22 _LIBCPP_PUSH_MACROS
23 #include <__undef_macros>
24 
25 _LIBCPP_BEGIN_NAMESPACE_STD
26 
27 template <class _BinaryPredicate, class _InputIterator, class _OutputIterator>
28 _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
29 __unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
30               input_iterator_tag, output_iterator_tag)
31 {
32     if (__first != __last)
33     {
34         typename iterator_traits<_InputIterator>::value_type __t(*__first);
35         *__result = __t;
36         ++__result;
37         while (++__first != __last)
38         {
39             if (!__pred(__t, *__first))
40             {
41                 __t = *__first;
42                 *__result = __t;
43                 ++__result;
44             }
45         }
46     }
47     return __result;
48 }
49 
50 template <class _BinaryPredicate, class _ForwardIterator, class _OutputIterator>
51 _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
52 __unique_copy(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
53               forward_iterator_tag, output_iterator_tag)
54 {
55     if (__first != __last)
56     {
57         _ForwardIterator __i = __first;
58         *__result = *__i;
59         ++__result;
60         while (++__first != __last)
61         {
62             if (!__pred(*__i, *__first))
63             {
64                 *__result = *__first;
65                 ++__result;
66                 __i = __first;
67             }
68         }
69     }
70     return __result;
71 }
72 
73 template <class _BinaryPredicate, class _InputIterator, class _ForwardIterator>
74 _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
75 __unique_copy(_InputIterator __first, _InputIterator __last, _ForwardIterator __result, _BinaryPredicate __pred,
76               input_iterator_tag, forward_iterator_tag)
77 {
78     if (__first != __last)
79     {
80         *__result = *__first;
81         while (++__first != __last)
82             if (!__pred(*__result, *__first))
83                 *++__result = *__first;
84         ++__result;
85     }
86     return __result;
87 }
88 
89 template <class _InputIterator, class _OutputIterator, class _BinaryPredicate>
90 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
91 _OutputIterator
92 unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred)
93 {
94     return _VSTD::__unique_copy<typename add_lvalue_reference<_BinaryPredicate>::type>
95                               (__first, __last, __result, __pred,
96                                typename iterator_traits<_InputIterator>::iterator_category(),
97                                typename iterator_traits<_OutputIterator>::iterator_category());
98 }
99 
100 template <class _InputIterator, class _OutputIterator>
101 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
102 _OutputIterator
103 unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
104 {
105     typedef typename iterator_traits<_InputIterator>::value_type __v;
106     return _VSTD::unique_copy(__first, __last, __result, __equal_to<__v>());
107 }
108 
109 
110 _LIBCPP_END_NAMESPACE_STD
111 
112 _LIBCPP_POP_MACROS
113 
114 #endif // _LIBCPP___ALGORITHM_UNIQUE_COPY_H
115