libcxx/include/__iterator/indirectly_comparable.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___ITERATOR_INDIRECTLY_COMPARABLE_H
  11 #define _LIBCPP___ITERATOR_INDIRECTLY_COMPARABLE_H
  12
  13 #include <__config>
  14 #include <__functional/identity.h>
  15 #include <__iterator/concepts.h>
  16 #include <__iterator/projected.h>
  17
  18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  19 #  pragma GCC system_header
  20 #endif
  21
  22 _LIBCPP_BEGIN_NAMESPACE_STD
  23
  24 #if _LIBCPP_STD_VER >= 20
  25
  26 template <class _I1, class _I2, class _Rp, class _P1 = identity, class _P2 = identity>
  27 concept indirectly_comparable =
  28   indirect_binary_predicate<_Rp, projected<_I1, _P1>, projected<_I2, _P2>>;
  29
  30 #endif // _LIBCPP_STD_VER >= 20
  31
  32 _LIBCPP_END_NAMESPACE_STD
  33
  34 #endif // _LIBCPP___ITERATOR_INDIRECTLY_COMPARABLE_H