libcxx/include/__cxx03/__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 <__cxx03/__config>
  13 #include <__cxx03/__iterator/concepts.h>
  14 #include <__cxx03/__iterator/incrementable_traits.h>
  15
  16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  17 #  pragma GCC system_header
  18 #endif
  19
  20 _LIBCPP_PUSH_MACROS
  21 #include <__cxx03/__undef_macros>
  22
  23 #if _LIBCPP_STD_VER >= 20
  24
  25 _LIBCPP_BEGIN_NAMESPACE_STD
  26
  27 namespace ranges {
  28 namespace __fill_n {
  29 struct __fn {
  30   template <class _Type, output_iterator<const _Type&> _Iter>
  31   _LIBCPP_HIDE_FROM_ABI constexpr _Iter
  32   operator()(_Iter __first, iter_difference_t<_Iter> __n, const _Type& __value) const {
  33     for (; __n != 0; --__n) {
  34       *__first = __value;
  35       ++__first;
  36     }
  37     return __first;
  38   }
  39 };
  40 } // namespace __fill_n
  41
  42 inline namespace __cpo {
  43 inline constexpr auto fill_n = __fill_n::__fn{};
  44 } // namespace __cpo
  45 } // namespace ranges
  46
  47 _LIBCPP_END_NAMESPACE_STD
  48
  49 #endif // _LIBCPP_STD_VER >= 20
  50
  51 _LIBCPP_POP_MACROS
  52
  53 #endif // _LIBCPP___ALGORITHM_RANGES_FILL_N_H