libcxx/include/__algorithm/ranges_fill_n.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___ALGORITHM_RANGES_FILL_N_H
  10 #define _LIBCPP___ALGORITHM_RANGES_FILL_N_H
  11
  12 #include <__config>
  13 #include <__iterator/concepts.h>
  14 #include <__iterator/incrementable_traits.h>
  15
  16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  17 #  pragma GCC system_header
  18 #endif
  19
  20 #if _LIBCPP_STD_VER >= 20
  21
  22 _LIBCPP_BEGIN_NAMESPACE_STD
  23
  24 namespace ranges {
  25 namespace __fill_n {
  26 struct __fn {
  27   template <class _Type, output_iterator<const _Type&> _Iter>
  28   _LIBCPP_HIDE_FROM_ABI constexpr _Iter
  29   operator()(_Iter __first, iter_difference_t<_Iter> __n, const _Type& __value) const {
  30     for (; __n != 0; --__n) {
  31       *__first = __value;
  32       ++__first;
  33     }
  34     return __first;
  35   }
  36 };
  37 } // namespace __fill_n
  38
  39 inline namespace __cpo {
  40 inline constexpr auto fill_n = __fill_n::__fn{};
  41 } // namespace __cpo
  42 } // namespace ranges
  43
  44 _LIBCPP_END_NAMESPACE_STD
  45
  46 #endif // _LIBCPP_STD_VER >= 20
  47
  48 #endif // _LIBCPP___ALGORITHM_RANGES_FILL_N_H