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 
22 template <class _Arg, class _Result>
23 struct _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 unary_function
24 {
25     typedef _Arg    argument_type;
26     typedef _Result result_type;
27 };
28 
29 #endif // _LIBCPP_STD_VER <= 14
30 
31 template <class _Arg, class _Result> struct __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")
41 template <class _Arg, class _Result>
42 using __unary_function = unary_function<_Arg, _Result>;
43 _LIBCPP_DIAGNOSTIC_POP
44 #else
45 template <class _Arg, class _Result>
46 using __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