xref: /llvm-project/libcxx/include/__algorithm/binary_search.h (revision 7ed7d4ccb8991e2b5b95334b508f8cec2faee737)
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 <__config>
13 #include <__algorithm/lower_bound.h>
14 #include <__algorithm/comp_ref_type.h>
15 #include <__iterator/iterator_traits.h>
16 
17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
18 #pragma GCC system_header
19 #endif
20 
21 _LIBCPP_PUSH_MACROS
22 #include <__undef_macros>
23 
24 _LIBCPP_BEGIN_NAMESPACE_STD
25 
26 template <class _Compare, class _ForwardIterator, class _Tp>
27 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
28 bool
29 __binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
30 {
31     __first = _VSTD::__lower_bound<_Compare>(__first, __last, __value_, __comp);
32     return __first != __last && !__comp(__value_, *__first);
33 }
34 
35 template <class _ForwardIterator, class _Tp, class _Compare>
36 _LIBCPP_NODISCARD_EXT inline
37 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
38 bool
39 binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
40 {
41     typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
42     return _VSTD::__binary_search<_Comp_ref>(__first, __last, __value_, __comp);
43 }
44 
45 template <class _ForwardIterator, class _Tp>
46 _LIBCPP_NODISCARD_EXT inline
47 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
48 bool
49 binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
50 {
51     return _VSTD::binary_search(__first, __last, __value_,
52                              __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
53 }
54 
55 
56 _LIBCPP_END_NAMESPACE_STD
57 
58 _LIBCPP_POP_MACROS
59 
60 #endif // _LIBCPP___ALGORITHM_BINARY_SEARCH_H
61