1*fe6060f1SDimitry Andric // -*- C++ -*- 2*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===// 3*fe6060f1SDimitry Andric // 4*fe6060f1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5*fe6060f1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 6*fe6060f1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7*fe6060f1SDimitry Andric // 8*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===// 9*fe6060f1SDimitry Andric 10*fe6060f1SDimitry Andric #ifndef _LIBCPP___RANGES_ENABLE_VIEW_H 11*fe6060f1SDimitry Andric #define _LIBCPP___RANGES_ENABLE_VIEW_H 12*fe6060f1SDimitry Andric 13*fe6060f1SDimitry Andric #include <__config> 14*fe6060f1SDimitry Andric #include <concepts> 15*fe6060f1SDimitry Andric 16*fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 17*fe6060f1SDimitry Andric #pragma GCC system_header 18*fe6060f1SDimitry Andric #endif 19*fe6060f1SDimitry Andric 20*fe6060f1SDimitry Andric _LIBCPP_PUSH_MACROS 21*fe6060f1SDimitry Andric #include <__undef_macros> 22*fe6060f1SDimitry Andric 23*fe6060f1SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 24*fe6060f1SDimitry Andric 25*fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_RANGES) 26*fe6060f1SDimitry Andric 27*fe6060f1SDimitry Andric namespace ranges { 28*fe6060f1SDimitry Andric 29*fe6060f1SDimitry Andric struct view_base { }; 30*fe6060f1SDimitry Andric 31*fe6060f1SDimitry Andric template <class _Tp> 32*fe6060f1SDimitry Andric inline constexpr bool enable_view = derived_from<_Tp, view_base>; 33*fe6060f1SDimitry Andric 34*fe6060f1SDimitry Andric } // end namespace ranges 35*fe6060f1SDimitry Andric 36*fe6060f1SDimitry Andric #endif // !_LIBCPP_HAS_NO_RANGES 37*fe6060f1SDimitry Andric 38*fe6060f1SDimitry Andric _LIBCPP_END_NAMESPACE_STD 39*fe6060f1SDimitry Andric 40*fe6060f1SDimitry Andric _LIBCPP_POP_MACROS 41*fe6060f1SDimitry Andric 42*fe6060f1SDimitry Andric #endif // _LIBCPP___RANGES_ENABLE_VIEW_H 43