libcxx/include/__fwd/subrange.h

   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___FWD_SUBRANGE_H
  10 #define _LIBCPP___FWD_SUBRANGE_H
  11
  12 #include <__config>
  13
  14 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  15 #  pragma GCC system_header
  16 #endif
  17
  18 #if _LIBCPP_STD_VER >= 20
  19
  20 #include <__iterator/concepts.h>
  21
  22 _LIBCPP_BEGIN_NAMESPACE_STD
  23
  24 namespace ranges {
  25
  26 enum class subrange_kind : bool { unsized, sized };
  27
  28 template <input_or_output_iterator _Iter, sentinel_for<_Iter> _Sent, subrange_kind _Kind>
  29   requires(_Kind == subrange_kind::sized || !sized_sentinel_for<_Sent, _Iter>)
  30 class _LIBCPP_TEMPLATE_VIS subrange;
  31
  32 } // namespace ranges
  33
  34 _LIBCPP_END_NAMESPACE_STD
  35
  36 #endif // _LIBCPP_STD_VER >= 20
  37
  38 #endif // _LIBCPP___FWD_SUBRANGE_H