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___TYPE_TRAITS_IS_SPECIALIZATION 11 #define _LIBCPP___TYPE_TRAITS_IS_SPECIALIZATION 12 13 // This contains parts of P2098R1 but is based on MSVC STL's implementation. 14 // 15 // The paper has been rejected 16 // We will not pursue P2098R0 (std::is_specialization_of) at this time; we'd 17 // like to see a solution to this problem, but it requires language evolution 18 // too. 19 // 20 // Since it is expected a real solution will be provided in the future only the 21 // minimal part is implemented. 22 // 23 // Note a cvref qualified _Tp is never considered a specialization. 24 25 #include <__config> 26 27 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 28 # pragma GCC system_header 29 #endif 30 31 _LIBCPP_BEGIN_NAMESPACE_STD 32 33 #if _LIBCPP_STD_VER > 14 34 35 template <class _Tp, template <class...> class _Template> 36 inline constexpr bool __is_specialization_v = false; // true if and only if _Tp is a specialization of _Template 37 38 template <template <class...> class _Template, class... _Args> 39 inline constexpr bool __is_specialization_v<_Template<_Args...>, _Template> = true; 40 41 #endif // _LIBCPP_STD_VER > 14 42 43 _LIBCPP_END_NAMESPACE_STD 44 45 #endif // _LIBCPP___TYPE_TRAITS_IS_SPECIALIZATION 46