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___TUPLE_PAIR_LIKE_H
10 #define _LIBCPP___TUPLE_PAIR_LIKE_H
11 
12 #include <__config>
13 #include <__tuple_dir/tuple_like.h>
14 #include <__tuple_dir/tuple_size.h>
15 #include <__type_traits/remove_cvref.h>
16 
17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
18 #  pragma GCC system_header
19 #endif
20 
21 _LIBCPP_BEGIN_NAMESPACE_STD
22 
23 #if _LIBCPP_STD_VER >= 20
24 
25 template <class _Tp>
26 concept __pair_like = __tuple_like<_Tp> && tuple_size<remove_cvref_t<_Tp>>::value == 2;
27 
28 #endif // _LIBCPP_STD_VER >= 20
29 
30 _LIBCPP_END_NAMESPACE_STD
31 
32 #endif // _LIBCPP___TUPLE_PAIR_LIKE_H
33