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___FUNCTIONAL_UNARY_FUNCTION_H
10#define _LIBCPP___FUNCTIONAL_UNARY_FUNCTION_H
11
12#include <__config>
13
14#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
15#  pragma GCC system_header
16#endif
17
18_LIBCPP_BEGIN_NAMESPACE_STD
19
20#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNARY_BINARY_FUNCTION)
21
22template <class _Arg, class _Result>
23struct _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 unary_function {
24  typedef _Arg argument_type;
25  typedef _Result result_type;
26};
27
28#endif // _LIBCPP_STD_VER <= 14
29
30template <class _Arg, class _Result>
31struct __unary_function_keep_layout_base {
32#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
33  using argument_type _LIBCPP_DEPRECATED_IN_CXX17 = _Arg;
34  using result_type _LIBCPP_DEPRECATED_IN_CXX17   = _Result;
35#endif
36};
37
38#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNARY_BINARY_FUNCTION)
39_LIBCPP_DIAGNOSTIC_PUSH
40_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wdeprecated-declarations")
41template <class _Arg, class _Result>
42using __unary_function = unary_function<_Arg, _Result>;
43_LIBCPP_DIAGNOSTIC_POP
44#else
45template <class _Arg, class _Result>
46using __unary_function = __unary_function_keep_layout_base<_Arg, _Result>;
47#endif
48
49_LIBCPP_END_NAMESPACE_STD
50
51#endif // _LIBCPP___FUNCTIONAL_UNARY_FUNCTION_H
52