libcxx/include/__functional/unary_negate.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___FUNCTIONAL_UNARY_NEGATE_H
  11 #define _LIBCPP___FUNCTIONAL_UNARY_NEGATE_H
  12
  13 #include <__config>
  14 #include <__functional/unary_function.h>
  15
  16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  17 #  pragma GCC system_header
  18 #endif
  19
  20 _LIBCPP_BEGIN_NAMESPACE_STD
  21
  22 #if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_NEGATORS)
  23
  24 template <class _Predicate>
  25 class _LIBCPP_TEMPLATE_VIS
  26 _LIBCPP_DEPRECATED_IN_CXX17 unary_negate : public __unary_function<typename _Predicate::argument_type, bool> {
  27   _Predicate __pred_;
  28
  29 public:
  30   _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI explicit unary_negate(const _Predicate& __pred)
  31       : __pred_(__pred) {}
  32   _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI bool
  33   operator()(const typename _Predicate::argument_type& __x) const {
  34     return !__pred_(__x);
  35   }
  36 };
  37
  38 template <class _Predicate>
  39 _LIBCPP_DEPRECATED_IN_CXX17 inline _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI unary_negate<_Predicate>
  40 not1(const _Predicate& __pred) {
  41   return unary_negate<_Predicate>(__pred);
  42 }
  43
  44 #endif // _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_NEGATORS)
  45
  46 _LIBCPP_END_NAMESPACE_STD
  47
  48 #endif // _LIBCPP___FUNCTIONAL_UNARY_NEGATE_H