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___TYPE_TRAITS_IS_REFERENCEABLE_H
10 #define _LIBCPP___TYPE_TRAITS_IS_REFERENCEABLE_H
11 
12 #include <__config>
13 #include <__type_traits/integral_constant.h>
14 #include <__type_traits/is_same.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 struct __is_referenceable_impl {
23     template <class _Tp> static _Tp& __test(int);
24     template <class _Tp> static false_type __test(...);
25 };
26 
27 template <class _Tp>
28 struct __is_referenceable : integral_constant<bool,
29     _IsNotSame<decltype(__is_referenceable_impl::__test<_Tp>(0)), false_type>::value> {};
30 
31 _LIBCPP_END_NAMESPACE_STD
32 
33 #endif // _LIBCPP___TYPE_TRAITS_IS_REFERENCEABLE_H
34