libcxx/include/__algorithm/adjacent_find.h

   1 // -*- C++ -*-
   2 //===----------------------------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef _LIBCPP___ALGORITHM_ADJACENT_FIND_H
  11 #define _LIBCPP___ALGORITHM_ADJACENT_FIND_H
  12
  13 #include <__algorithm/comp.h>
  14 #include <__algorithm/iterator_operations.h>
  15 #include <__config>
  16 #include <__functional/identity.h>
  17 #include <__iterator/iterator_traits.h>
  18 #include <__type_traits/invoke.h>
  19 #include <__utility/move.h>
  20
  21 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  22 #  pragma GCC system_header
  23 #endif
  24
  25 _LIBCPP_PUSH_MACROS
  26 #include <__undef_macros>
  27
  28 _LIBCPP_BEGIN_NAMESPACE_STD
  29
  30 template <class _Iter, class _Sent, class _Pred, class _Proj>
  31 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter
  32 __adjacent_find(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) {
  33   if (__first == __last)
  34     return __first;
  35
  36   _Iter __i = __first;
  37   while (++__i != __last) {
  38     if (std::__invoke(__pred, std::__invoke(__proj, *__first), std::__invoke(__proj, *__i)))
  39       return __first;
  40     __first = __i;
  41   }
  42   return __i;
  43 }
  44
  45 template <class _ForwardIterator, class _BinaryPredicate>
  46 [[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
  47 adjacent_find(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred) {
  48   __identity __proj;
  49   return std::__adjacent_find(std::move(__first), std::move(__last), __pred, __proj);
  50 }
  51
  52 template <class _ForwardIterator>
  53 [[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
  54 adjacent_find(_ForwardIterator __first, _ForwardIterator __last) {
  55   return std::adjacent_find(std::move(__first), std::move(__last), __equal_to());
  56 }
  57
  58 _LIBCPP_END_NAMESPACE_STD
  59
  60 _LIBCPP_POP_MACROS
  61
  62 #endif // _LIBCPP___ALGORITHM_ADJACENT_FIND_H