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___FUNCTIONAL_IS_TRANSPARENT 11 #define _LIBCPP___FUNCTIONAL_IS_TRANSPARENT 12 13 #include <__config> 14 #include <type_traits> 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 #if _LIBCPP_STD_VER > 11 23 24 template <class _Tp, class, class = void> 25 struct __is_transparent : false_type {}; 26 27 template <class _Tp, class _Up> 28 struct __is_transparent<_Tp, _Up, 29 typename __void_t<typename _Tp::is_transparent>::type> 30 : true_type {}; 31 32 #endif 33 34 _LIBCPP_END_NAMESPACE_STD 35 36 #endif // _LIBCPP___FUNCTIONAL_IS_TRANSPARENT 37