xref: /llvm-project/libcxx/include/__algorithm/binary_search.h (revision 5aaefa510ef055e8f044ca89e352d4313f3aba49)
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_BINARY_SEARCH_H
10 #define _LIBCPP___ALGORITHM_BINARY_SEARCH_H
11 
12 #include <__algorithm/comp.h>
13 #include <__algorithm/comp_ref_type.h>
14 #include <__algorithm/lower_bound.h>
15 #include <__config>
16 #include <__iterator/iterator_traits.h>
17 
18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19 #  pragma GCC system_header
20 #  pragma clang include_instead(<algorithm>)
21 #endif
22 
23 _LIBCPP_BEGIN_NAMESPACE_STD
24 
25 template <class _Compare, class _ForwardIterator, class _Tp>
26 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
27 bool
28 __binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
29 {
30     __first = _VSTD::__lower_bound<_Compare>(__first, __last, __value_, __comp);
31     return __first != __last && !__comp(__value_, *__first);
32 }
33 
34 template <class _ForwardIterator, class _Tp, class _Compare>
35 _LIBCPP_NODISCARD_EXT inline
36 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
37 bool
38 binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
39 {
40     typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
41     return _VSTD::__binary_search<_Comp_ref>(__first, __last, __value_, __comp);
42 }
43 
44 template <class _ForwardIterator, class _Tp>
45 _LIBCPP_NODISCARD_EXT inline
46 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
47 bool
48 binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
49 {
50     return _VSTD::binary_search(__first, __last, __value_,
51                              __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
52 }
53 
54 _LIBCPP_END_NAMESPACE_STD
55 
56 #endif // _LIBCPP___ALGORITHM_BINARY_SEARCH_H
57