1// -*- C++ -*-
  2//===----------------------------------------------------------------------===//
  3//
  4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  5// See https://llvm.org/LICENSE.txt for license information.
  6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  7//
  8//===----------------------------------------------------------------------===//
  9
 10#ifndef _LIBCPP___RANGES_DATA_H
 11#define _LIBCPP___RANGES_DATA_H
 12
 13#include <__concepts/class_or_enum.h>
 14#include <__config>
 15#include <__iterator/concepts.h>
 16#include <__iterator/iterator_traits.h>
 17#include <__memory/pointer_traits.h>
 18#include <__ranges/access.h>
 19#include <__type_traits/decay.h>
 20#include <__type_traits/is_object.h>
 21#include <__type_traits/is_pointer.h>
 22#include <__type_traits/is_reference.h>
 23#include <__type_traits/remove_pointer.h>
 24#include <__type_traits/remove_reference.h>
 25#include <__utility/auto_cast.h>
 26
 27#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 28#  pragma GCC system_header
 29#endif
 30
 31_LIBCPP_BEGIN_NAMESPACE_STD
 32
 33#if _LIBCPP_STD_VER >= 20
 34
 35// [range.prim.data]
 36
 37namespace ranges {
 38namespace __data {
 39template <class _Tp>
 40concept __ptr_to_object = is_pointer_v<_Tp> && is_object_v<remove_pointer_t<_Tp>>;
 41
 42template <class _Tp>
 43concept __member_data = __can_borrow<_Tp> && requires(_Tp&& __t) {
 44  { _LIBCPP_AUTO_CAST(__t.data()) } -> __ptr_to_object;
 45};
 46
 47template <class _Tp>
 48concept __ranges_begin_invocable = !__member_data<_Tp> && __can_borrow<_Tp> && requires(_Tp&& __t) {
 49  { ranges::begin(__t) } -> contiguous_iterator;
 50};
 51
 52struct __fn {
 53  template <__member_data _Tp>
 54  _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const noexcept(noexcept(__t.data())) {
 55    return __t.data();
 56  }
 57
 58  template <__ranges_begin_invocable _Tp>
 59  _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
 60      noexcept(noexcept(std::to_address(ranges::begin(__t)))) {
 61    return std::to_address(ranges::begin(__t));
 62  }
 63};
 64} // namespace __data
 65
 66inline namespace __cpo {
 67inline constexpr auto data = __data::__fn{};
 68} // namespace __cpo
 69} // namespace ranges
 70
 71// [range.prim.cdata]
 72
 73namespace ranges {
 74namespace __cdata {
 75struct __fn {
 76  template <class _Tp>
 77    requires is_lvalue_reference_v<_Tp&&>
 78  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const
 79      noexcept(noexcept(ranges::data(static_cast<const remove_reference_t<_Tp>&>(__t))))
 80          -> decltype(ranges::data(static_cast<const remove_reference_t<_Tp>&>(__t))) {
 81    return ranges::data(static_cast<const remove_reference_t<_Tp>&>(__t));
 82  }
 83
 84  template <class _Tp>
 85    requires is_rvalue_reference_v<_Tp&&>
 86  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const noexcept(
 87      noexcept(ranges::data(static_cast<const _Tp&&>(__t)))) -> decltype(ranges::data(static_cast<const _Tp&&>(__t))) {
 88    return ranges::data(static_cast<const _Tp&&>(__t));
 89  }
 90};
 91} // namespace __cdata
 92
 93inline namespace __cpo {
 94inline constexpr auto cdata = __cdata::__fn{};
 95} // namespace __cpo
 96} // namespace ranges
 97
 98#endif // _LIBCPP_STD_VER >= 20
 99
100_LIBCPP_END_NAMESPACE_STD
101
102#endif // _LIBCPP___RANGES_DATA_H