| // -*- C++ -*- |
| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef _LIBCPP___RANGES_ENABLE_VIEW_H |
| #define _LIBCPP___RANGES_ENABLE_VIEW_H |
| |
| #include <__config> |
| #include <concepts> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| #pragma GCC system_header |
| #endif |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| #if !defined(_LIBCPP_HAS_NO_RANGES) |
| |
| namespace ranges { |
| |
| struct view_base { }; |
| |
| template <class _Tp> |
| inline constexpr bool enable_view = derived_from<_Tp, view_base>; |
| |
| } // end namespace ranges |
| |
| #endif // !_LIBCPP_HAS_NO_RANGES |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // _LIBCPP___RANGES_ENABLE_VIEW_H |
