range_access.h
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// Range access functions for containers -*- C++ -*-
// Copyright (C) 2010-2021 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file bits/range_access.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{iterator}
*/
#ifndef _GLIBCXX_RANGE_ACCESS_H
#define _GLIBCXX_RANGE_ACCESS_H 1
#pragma GCC system_header
#if __cplusplus >= 201103L
#include <initializer_list>
#include <type_traits> // common_type_t, make_signed_t
#include <bits/stl_iterator.h> // reverse_iterator
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @brief Return an iterator pointing to the first element of
* the container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
begin(_Container& __cont) -> decltype(__cont.begin())
{ return __cont.begin(); }
/**
* @brief Return an iterator pointing to the first element of
* the const container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
begin(const _Container& __cont) -> decltype(__cont.begin())
{ return __cont.begin(); }
/**
* @brief Return an iterator pointing to one past the last element of
* the container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
end(_Container& __cont) -> decltype(__cont.end())
{ return __cont.end(); }
/**
* @brief Return an iterator pointing to one past the last element of
* the const container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
end(const _Container& __cont) -> decltype(__cont.end())
{ return __cont.end(); }
/**
* @brief Return an iterator pointing to the first element of the array.
* @param __arr Array.
*/
template<typename _Tp, size_t _Nm>
inline _GLIBCXX14_CONSTEXPR _Tp*
begin(_Tp (&__arr)[_Nm]) noexcept
{ return __arr; }
/**
* @brief Return an iterator pointing to one past the last element
* of the array.
* @param __arr Array.
*/
template<typename _Tp, size_t _Nm>
inline _GLIBCXX14_CONSTEXPR _Tp*
end(_Tp (&__arr)[_Nm]) noexcept
{ return __arr + _Nm; }
#if __cplusplus >= 201402L
template<typename _Tp> class valarray;
// These overloads must be declared for cbegin and cend to use them.
template<typename _Tp> _Tp* begin(valarray<_Tp>&) noexcept;
template<typename _Tp> const _Tp* begin(const valarray<_Tp>&) noexcept;
template<typename _Tp> _Tp* end(valarray<_Tp>&) noexcept;
template<typename _Tp> const _Tp* end(const valarray<_Tp>&) noexcept;
/**
* @brief Return an iterator pointing to the first element of
* the const container.
* @param __cont Container.
*/
template<typename _Container>
inline constexpr auto
cbegin(const _Container& __cont) noexcept(noexcept(std::begin(__cont)))
-> decltype(std::begin(__cont))
{ return std::begin(__cont); }
/**
* @brief Return an iterator pointing to one past the last element of
* the const container.
* @param __cont Container.
*/
template<typename _Container>
inline constexpr auto
cend(const _Container& __cont) noexcept(noexcept(std::end(__cont)))
-> decltype(std::end(__cont))
{ return std::end(__cont); }
/**
* @brief Return a reverse iterator pointing to the last element of
* the container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
rbegin(_Container& __cont) -> decltype(__cont.rbegin())
{ return __cont.rbegin(); }
/**
* @brief Return a reverse iterator pointing to the last element of
* the const container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
rbegin(const _Container& __cont) -> decltype(__cont.rbegin())
{ return __cont.rbegin(); }
/**
* @brief Return a reverse iterator pointing one past the first element of
* the container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
rend(_Container& __cont) -> decltype(__cont.rend())
{ return __cont.rend(); }
/**
* @brief Return a reverse iterator pointing one past the first element of
* the const container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
rend(const _Container& __cont) -> decltype(__cont.rend())
{ return __cont.rend(); }
/**
* @brief Return a reverse iterator pointing to the last element of
* the array.
* @param __arr Array.
*/
template<typename _Tp, size_t _Nm>
inline _GLIBCXX17_CONSTEXPR reverse_iterator<_Tp*>
rbegin(_Tp (&__arr)[_Nm]) noexcept
{ return reverse_iterator<_Tp*>(__arr + _Nm); }
/**
* @brief Return a reverse iterator pointing one past the first element of
* the array.
* @param __arr Array.
*/
template<typename _Tp, size_t _Nm>
inline _GLIBCXX17_CONSTEXPR reverse_iterator<_Tp*>
rend(_Tp (&__arr)[_Nm]) noexcept
{ return reverse_iterator<_Tp*>(__arr); }
/**
* @brief Return a reverse iterator pointing to the last element of
* the initializer_list.
* @param __il initializer_list.
*/
template<typename _Tp>
inline _GLIBCXX17_CONSTEXPR reverse_iterator<const _Tp*>
rbegin(initializer_list<_Tp> __il) noexcept
{ return reverse_iterator<const _Tp*>(__il.end()); }
/**
* @brief Return a reverse iterator pointing one past the first element of
* the initializer_list.
* @param __il initializer_list.
*/
template<typename _Tp>
inline _GLIBCXX17_CONSTEXPR reverse_iterator<const _Tp*>
rend(initializer_list<_Tp> __il) noexcept
{ return reverse_iterator<const _Tp*>(__il.begin()); }
/**
* @brief Return a reverse iterator pointing to the last element of
* the const container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
crbegin(const _Container& __cont) -> decltype(std::rbegin(__cont))
{ return std::rbegin(__cont); }
/**
* @brief Return a reverse iterator pointing one past the first element of
* the const container.
* @param __cont Container.
*/
template<typename _Container>
inline _GLIBCXX17_CONSTEXPR auto
crend(const _Container& __cont) -> decltype(std::rend(__cont))
{ return std::rend(__cont); }
#endif // C++14
#if __cplusplus >= 201703L
#define __cpp_lib_nonmember_container_access 201411
/**
* @brief Return the size of a container.
* @param __cont Container.
*/
template <typename _Container>
constexpr auto
size(const _Container& __cont) noexcept(noexcept(__cont.size()))
-> decltype(__cont.size())
{ return __cont.size(); }
/**
* @brief Return the size of an array.
*/
template <typename _Tp, size_t _Nm>
constexpr size_t
size(const _Tp (&)[_Nm]) noexcept
{ return _Nm; }
/**
* @brief Return whether a container is empty.
* @param __cont Container.
*/
template <typename _Container>
[[nodiscard]] constexpr auto
empty(const _Container& __cont) noexcept(noexcept(__cont.empty()))
-> decltype(__cont.empty())
{ return __cont.empty(); }
/**
* @brief Return whether an array is empty (always false).
*/
template <typename _Tp, size_t _Nm>
[[nodiscard]] constexpr bool
empty(const _Tp (&)[_Nm]) noexcept
{ return false; }
/**
* @brief Return whether an initializer_list is empty.
* @param __il Initializer list.
*/
template <typename _Tp>
[[nodiscard]] constexpr bool
empty(initializer_list<_Tp> __il) noexcept
{ return __il.size() == 0;}
/**
* @brief Return the data pointer of a container.
* @param __cont Container.
*/
template <typename _Container>
constexpr auto
data(_Container& __cont) noexcept(noexcept(__cont.data()))
-> decltype(__cont.data())
{ return __cont.data(); }
/**
* @brief Return the data pointer of a const container.
* @param __cont Container.
*/
template <typename _Container>
constexpr auto
data(const _Container& __cont) noexcept(noexcept(__cont.data()))
-> decltype(__cont.data())
{ return __cont.data(); }
/**
* @brief Return the data pointer of an array.
* @param __array Array.
*/
template <typename _Tp, size_t _Nm>
constexpr _Tp*
data(_Tp (&__array)[_Nm]) noexcept
{ return __array; }
/**
* @brief Return the data pointer of an initializer list.
* @param __il Initializer list.
*/
template <typename _Tp>
constexpr const _Tp*
data(initializer_list<_Tp> __il) noexcept
{ return __il.begin(); }
#if __cplusplus > 201703L
#define __cpp_lib_ssize 201902L
template<typename _Container>
constexpr auto
ssize(const _Container& __cont)
noexcept(noexcept(__cont.size()))
-> common_type_t<ptrdiff_t, make_signed_t<decltype(__cont.size())>>
{
using type = make_signed_t<decltype(__cont.size())>;
return static_cast<common_type_t<ptrdiff_t, type>>(__cont.size());
}
template<typename _Tp, ptrdiff_t _Num>
constexpr ptrdiff_t
ssize(const _Tp (&)[_Num]) noexcept
{ return _Num; }
#endif // C++20
#endif // C++17
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif // C++11
#endif // _GLIBCXX_RANGE_ACCESS_H
initializer_list
std::common_type_t
typename common_type< _Tp... >::type common_type_t
Alias template for common_type.
Definition: type_traits:2593
std::make_signed_t
typename make_signed< _Tp >::type make_signed_t
Alias template for make_signed.
Definition: type_traits:1976
std::end
_Tp * end(valarray< _Tp > &__va) noexcept
Return an iterator pointing to one past the last element of the valarray.
Definition: valarray:1237
std::begin
_Tp * begin(valarray< _Tp > &__va) noexcept
Return an iterator pointing to the first element of the valarray.
Definition: valarray:1215
std
ISO C++ entities toplevel namespace is std.
std::crend
constexpr auto crend(const _Container &__cont) -> decltype(std::rend(__cont))
Return a reverse iterator pointing one past the first element of the const container.
Definition: range_access.h:231
std::rend
constexpr auto rend(_Container &__cont) -> decltype(__cont.rend())
Return a reverse iterator pointing one past the first element of the container.
Definition: range_access.h:161
std::cend
constexpr auto cend(const _Container &__cont) noexcept(noexcept(std::end(__cont))) -> decltype(std::end(__cont))
Return an iterator pointing to one past the last element of the const container.
Definition: range_access.h:130
std::empty
constexpr auto empty(const _Container &__cont) noexcept(noexcept(__cont.empty())) -> decltype(__cont.empty())
Return whether a container is empty.
Definition: range_access.h:263
std::size
constexpr auto size(const _Container &__cont) noexcept(noexcept(__cont.size())) -> decltype(__cont.size())
Return the size of a container.
Definition: range_access.h:245
std::rbegin
constexpr auto rbegin(_Container &__cont) -> decltype(__cont.rbegin())
Return a reverse iterator pointing to the last element of the container.
Definition: range_access.h:141
std::crbegin
constexpr auto crbegin(const _Container &__cont) -> decltype(std::rbegin(__cont))
Return a reverse iterator pointing to the last element of the const container.
Definition: range_access.h:221
std::data
constexpr auto data(_Container &__cont) noexcept(noexcept(__cont.data())) -> decltype(__cont.data())
Return the data pointer of a container.
Definition: range_access.h:290
std::cbegin
constexpr auto cbegin(const _Container &__cont) noexcept(noexcept(std::begin(__cont))) -> decltype(std::begin(__cont))
Return an iterator pointing to the first element of the const container.
Definition: range_access.h:119
std::initializer_list
initializer_list
Definition: initializer_list:48
std::reverse_iterator
Definition: bits/stl_iterator.h:133
stl_iterator.h
type_traits