// List implementation -*- C++ -*-
// Copyright (C) 2001-2025 Free Software Foundation, Inc.
// Copyright The GNU Toolchain Authors.
//
// 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
// .
/*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996,1997
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file bits/stl_list.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{list}
*/
#ifndef _STL_LIST_H
#define _STL_LIST_H 1
#include
#include
#include
#if __cplusplus >= 201103L
#include
#include
#include
#include
#endif
#if __glibcxx_containers_ranges // C++ >= 23
# include // ranges::begin, ranges::distance etc.
# include // ranges::subrange
#endif
#if __cplusplus < 201103L
# undef _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
# define _GLIBCXX_USE_ALLOC_PTR_FOR_LIST 0
#elif ! defined _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
# define _GLIBCXX_USE_ALLOC_PTR_FOR_LIST 1
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
namespace __detail
{
// Supporting structures are split into common and templated
// types; the latter publicly inherits from the former in an
// effort to reduce code duplication. This results in some
// "needless" static_cast'ing later on, but it's all safe
// downcasting.
/// Common part of a node in the %list.
struct _List_node_base
{
typedef _List_node_base* _Base_ptr;
_List_node_base* _M_next;
_List_node_base* _M_prev;
static void
swap(_List_node_base& __x, _List_node_base& __y) _GLIBCXX_USE_NOEXCEPT;
void
_M_transfer(_List_node_base* const __first,
_List_node_base* const __last) _GLIBCXX_USE_NOEXCEPT;
void
_M_reverse() _GLIBCXX_USE_NOEXCEPT;
void
_M_hook(_List_node_base* const __position) _GLIBCXX_USE_NOEXCEPT;
void
_M_unhook() _GLIBCXX_USE_NOEXCEPT;
_List_node_base* _M_base() { return this; }
const _List_node_base* _M_base() const { return this; }
};
struct _List_size
{
#if _GLIBCXX_USE_CXX11_ABI
// Store the size here so that std::list::size() is fast.
size_t _M_size;
#endif
};
/// The %list node header.
struct _List_node_header : public _List_node_base, _List_size
{
_List_node_header() _GLIBCXX_NOEXCEPT
{ _M_init(); }
#if __cplusplus >= 201103L
_List_node_header(_List_node_header&& __x) noexcept
: _List_node_base(__x), _List_size(__x)
{
if (__x._M_base()->_M_next == __x._M_base())
this->_M_next = this->_M_prev = this;
else
{
this->_M_next->_M_prev = this->_M_prev->_M_next = this->_M_base();
__x._M_init();
}
}
void
_M_move_nodes(_List_node_header&& __x)
{
_List_node_base* const __xnode = __x._M_base();
if (__xnode->_M_next == __xnode)
_M_init();
else
{
_List_node_base* const __node = this->_M_base();
__node->_M_next = __xnode->_M_next;
__node->_M_prev = __xnode->_M_prev;
__node->_M_next->_M_prev = __node->_M_prev->_M_next = __node;
_List_size::operator=(__x);
__x._M_init();
}
}
#endif
void
_M_init() _GLIBCXX_NOEXCEPT
{
this->_M_next = this->_M_prev = this;
_List_size::operator=(_List_size());
}
using _List_node_base::_M_base;
#if ! _GLIBCXX_INLINE_VERSION
_List_node_base* _M_base() { return this; } // XXX GLIBCXX_ABI Deprecated
#endif
};
} // namespace detail
#if _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_GLIBCXX_BEGIN_NAMESPACE_CXX11
template class list;
_GLIBCXX_END_NAMESPACE_CXX11
_GLIBCXX_END_NAMESPACE_CONTAINER
namespace __list
{
// The base class for a list node. Contains the pointers connecting nodes.
template
struct _Node_base
{
using _Base_ptr = __ptr_rebind<_VoidPtr, _Node_base>;
_Base_ptr _M_next;
_Base_ptr _M_prev;
static void
swap(_Node_base& __x, _Node_base& __y) noexcept;
void
_M_transfer(_Base_ptr const __first, _Base_ptr const __last) noexcept;
void
_M_hook(_Base_ptr const __position) noexcept
{
auto __self = this->_M_base();
this->_M_next = __position;
this->_M_prev = __position->_M_prev;
__position->_M_prev->_M_next = __self;
__position->_M_prev = __self;
}
void
_M_unhook() noexcept
{
auto const __next_node = this->_M_next;
auto const __prev_node = this->_M_prev;
__prev_node->_M_next = __next_node;
__next_node->_M_prev = __prev_node;
}
// This is not const-correct, but it's only used in a const access path
// by std::list::empty(), where it doesn't escape, and by
// std::list::end() const, where the pointer is used to initialize a
// const_iterator and so constness is restored.
// The standard allows pointer_to to be potentially-throwing,
// but we have to assume it doesn't throw to implement std::list.
_Base_ptr
_M_base() const noexcept
{
return pointer_traits<_Base_ptr>::
pointer_to(const_cast<_Node_base&>(*this));
}
};
using ::std::__detail::_List_size;
// The special sentinel node contained by a std::list.
// begin()->_M_node->_M_prev and end()->_M_node point to this header.
// This is not a complete node, as it doesn't contain a value.
template
struct _Node_header
: public _Node_base<_VoidPtr>, _List_size
{
_Node_header() noexcept
{ _M_init(); }
_Node_header(_Node_header&& __x) noexcept
: _Node_base<_VoidPtr>(__x), _List_size(__x)
{
if (__x._M_base()->_M_next == __x._M_base())
this->_M_next = this->_M_prev = this->_M_base();
else
{
this->_M_next->_M_prev = this->_M_prev->_M_next = this->_M_base();
__x._M_init();
}
}
void
_M_move_nodes(_Node_header&& __x) noexcept
{
auto const __xnode = __x._M_base();
if (__xnode->_M_next == __xnode)
_M_init();
else
{
auto const __node = this->_M_base();
__node->_M_next = __xnode->_M_next;
__node->_M_prev = __xnode->_M_prev;
__node->_M_next->_M_prev = __node->_M_prev->_M_next = __node;
_List_size::operator=(__x);
__x._M_init();
}
}
void
_M_init() noexcept
{
this->_M_next = this->_M_prev = this->_M_base();
_List_size::operator=(_List_size());
}
void _M_reverse() noexcept;
};
// The node type used for allocators with fancy pointers.
template
struct _Node : public __list::_Node_base<__ptr_rebind<_ValPtr, void>>
{
using value_type = typename pointer_traits<_ValPtr>::element_type;
using _Node_ptr = __ptr_rebind<_ValPtr, _Node>;
_Node() noexcept { }
~_Node() { }
_Node(_Node&&) = delete;
union _Uninit_storage
{
_Uninit_storage() noexcept { }
~_Uninit_storage() { }
value_type _M_data;
};
_Uninit_storage _M_u;
value_type*
_M_valptr() noexcept { return std::__addressof(_M_u._M_data); }
value_type const*
_M_valptr() const noexcept { return std::__addressof(_M_u._M_data); }
_Node_ptr
_M_node_ptr()
{ return pointer_traits<_Node_ptr>::pointer_to(*this); }
};
template class _Iterator;
template
class _Iterator
{
using _Node = __list::_Node<_Ptr>;
using _Base_ptr
= typename __list::_Node_base<__ptr_rebind<_Ptr, void>>::_Base_ptr;
template
using __maybe_const = __conditional_t<_Const, const _Tp, _Tp>;
public:
using value_type = typename pointer_traits<_Ptr>::element_type;
using difference_type = ptrdiff_t;
using iterator_category = bidirectional_iterator_tag;
using pointer = __maybe_const*;
using reference = __maybe_const&;
constexpr _Iterator() noexcept : _M_node() { }
_Iterator(const _Iterator&) = default;
_Iterator& operator=(const _Iterator&) = default;
#ifdef __glibcxx_concepts
constexpr
_Iterator(const _Iterator& __i) requires _Const
#else
template>
constexpr
_Iterator(const _Iterator<_OtherConst, _Ptr>& __i)
#endif
: _M_node(__i._M_node) { }
constexpr explicit
_Iterator(_Base_ptr __x) noexcept
: _M_node(__x) { }
// Must downcast from _Node_base to _Node to get to value.
[[__nodiscard__]]
constexpr reference
operator*() const noexcept
{ return static_cast<_Node&>(*_M_node)._M_u._M_data; }
[[__nodiscard__]]
constexpr pointer
operator->() const noexcept
{ return std::__addressof(operator*()); }
_GLIBCXX14_CONSTEXPR _Iterator&
operator++() noexcept
{
_M_node = _M_node->_M_next;
return *this;
}
_GLIBCXX14_CONSTEXPR _Iterator
operator++(int) noexcept
{
auto __tmp = *this;
_M_node = _M_node->_M_next;
return __tmp;
}
_GLIBCXX14_CONSTEXPR _Iterator&
operator--() noexcept
{
_M_node = _M_node->_M_prev;
return *this;
}
_GLIBCXX14_CONSTEXPR _Iterator
operator--(int) noexcept
{
auto __tmp = *this;
_M_node = _M_node->_M_prev;
return __tmp;
}
[[__nodiscard__]]
friend constexpr bool
operator==(const _Iterator& __x, const _Iterator& __y) noexcept
{ return __x._M_node == __y._M_node; }
#if __cpp_impl_three_way_comparison < 201907L
[[__nodiscard__]]
friend constexpr bool
operator!=(const _Iterator& __x, const _Iterator& __y) noexcept
{ return __x._M_node != __y._M_node; }
#endif
private:
template
friend class _GLIBCXX_STD_C::list;
friend _Iterator;
constexpr _Iterator
_M_const_cast() const noexcept
{ return _Iterator(_M_node); }
_Base_ptr _M_node;
};
} // namespace __list
#endif // USE_ALLOC_PTR_FOR_LIST
_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
template struct _List_node;
template struct _List_iterator;
template struct _List_const_iterator;
_GLIBCXX_END_NAMESPACE_CONTAINER
namespace __list
{
// Determine the node and iterator types used by std::list.
template
struct _Node_traits;
#if _GLIBCXX_USE_ALLOC_PTR_FOR_LIST <= 9000
// Specialization for the simple case where the allocator's pointer type
// is the same type as value_type*.
// For ABI compatibility we can't change the types used for this case.
template
struct _Node_traits<_Tp, _Tp*>
{
typedef __detail::_List_node_base _Node_base;
typedef __detail::_List_node_header _Node_header;
typedef _GLIBCXX_STD_C::_List_node<_Tp> _Node;
typedef _GLIBCXX_STD_C::_List_iterator<_Tp> _Iterator;
typedef _GLIBCXX_STD_C::_List_const_iterator<_Tp> _Const_iterator;
};
#endif
#if ! _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
// Always use the T* specialization.
template
struct _Node_traits
: _Node_traits<_Tp, _Tp*>
{ };
#else
// Primary template used when the allocator uses fancy pointers.
template
struct _Node_traits
{
private:
using _VoidPtr = __ptr_rebind<_Ptr, void>;
using _ValPtr = __ptr_rebind<_Ptr, _Tp>;
public:
using _Node_base = __list::_Node_base<_VoidPtr>;
using _Node_header = __list::_Node_header<_VoidPtr>;
using _Node = __list::_Node<_ValPtr>;
using _Iterator = __list::_Iterator;
using _Const_iterator = __list::_Iterator;
};
#endif // USE_ALLOC_PTR_FOR_LIST
// Used by std::list::sort to hold nodes being sorted.
template
struct _Scratch_list
: _NodeBaseT
{
typedef _NodeBaseT _Base;
typedef typename _Base::_Base_ptr _Base_ptr;
_Scratch_list() { this->_M_next = this->_M_prev = this->_M_base(); }
bool empty() const { return this->_M_next == this->_M_base(); }
void swap(_Base& __l) { _Base::swap(*this, __l); }
template
struct _Ptr_cmp
{
_Cmp _M_cmp;
bool
operator()(_Base_ptr __lhs, _Base_ptr __rhs) /* not const */
{ return _M_cmp(*_Iter(__lhs), *_Iter(__rhs)); }
};
template
struct _Ptr_cmp<_Iter, void>
{
bool
operator()(_Base_ptr __lhs, _Base_ptr __rhs) const
{ return *_Iter(__lhs) < *_Iter(__rhs); }
};
// Merge nodes from __x into *this. Both lists must be sorted wrt _Cmp.
template
void
merge(_Base& __x, _Cmp __comp)
{
_Base_ptr __first1 = this->_M_next;
_Base_ptr const __last1 = this->_M_base();
_Base_ptr __first2 = __x._M_next;
_Base_ptr const __last2 = __x._M_base();
while (__first1 != __last1 && __first2 != __last2)
{
if (__comp(__first2, __first1))
{
_Base_ptr __next = __first2->_M_next;
__first1->_M_transfer(__first2, __next);
__first2 = __next;
}
else
__first1 = __first1->_M_next;
}
if (__first2 != __last2)
this->_M_transfer(__first2, __last2);
}
// Splice the node at __i into *this.
void _M_take_one(_Base_ptr __i)
{ this->_M_transfer(__i, __i->_M_next); }
// Splice all nodes from *this after __i.
void _M_put_all(_Base_ptr __i)
{
if (!empty())
__i->_M_transfer(this->_M_next, this->_M_base());
}
};
} // namespace __list
_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
/// An actual node in the %list.
template
struct _List_node : public __detail::_List_node_base
{
typedef _List_node* _Node_ptr;
#if __cplusplus >= 201103L
__gnu_cxx::__aligned_membuf<_Tp> _M_storage;
_Tp* _M_valptr() { return _M_storage._M_ptr(); }
_Tp const* _M_valptr() const { return _M_storage._M_ptr(); }
#else
_Tp _M_data;
_Tp* _M_valptr() { return std::__addressof(_M_data); }
_Tp const* _M_valptr() const { return std::__addressof(_M_data); }
#endif
_Node_ptr _M_node_ptr() { return this; }
};
/**
* @brief A list::iterator.
*
* All the functions are op overloads.
*/
template
struct _List_iterator
{
typedef _List_node<_Tp> _Node;
typedef ptrdiff_t difference_type;
typedef std::bidirectional_iterator_tag iterator_category;
typedef _Tp value_type;
typedef _Tp* pointer;
typedef _Tp& reference;
_List_iterator() _GLIBCXX_NOEXCEPT
: _M_node() { }
explicit
_List_iterator(__detail::_List_node_base* __x) _GLIBCXX_NOEXCEPT
: _M_node(__x) { }
_List_iterator
_M_const_cast() const _GLIBCXX_NOEXCEPT
{ return *this; }
// Must downcast from _List_node_base to _List_node to get to value.
_GLIBCXX_NODISCARD
reference
operator*() const _GLIBCXX_NOEXCEPT
{ return *static_cast<_Node*>(_M_node)->_M_valptr(); }
_GLIBCXX_NODISCARD
pointer
operator->() const _GLIBCXX_NOEXCEPT
{ return static_cast<_Node*>(_M_node)->_M_valptr(); }
_List_iterator&
operator++() _GLIBCXX_NOEXCEPT
{
_M_node = _M_node->_M_next;
return *this;
}
_List_iterator
operator++(int) _GLIBCXX_NOEXCEPT
{
_List_iterator __tmp = *this;
_M_node = _M_node->_M_next;
return __tmp;
}
_List_iterator&
operator--() _GLIBCXX_NOEXCEPT
{
_M_node = _M_node->_M_prev;
return *this;
}
_List_iterator
operator--(int) _GLIBCXX_NOEXCEPT
{
_List_iterator __tmp = *this;
_M_node = _M_node->_M_prev;
return __tmp;
}
_GLIBCXX_NODISCARD
friend bool
operator==(const _List_iterator& __x,
const _List_iterator& __y) _GLIBCXX_NOEXCEPT
{ return __x._M_node == __y._M_node; }
#if __cpp_impl_three_way_comparison < 201907L
_GLIBCXX_NODISCARD
friend bool
operator!=(const _List_iterator& __x,
const _List_iterator& __y) _GLIBCXX_NOEXCEPT
{ return __x._M_node != __y._M_node; }
#endif
// The only member points to the %list element.
__detail::_List_node_base* _M_node;
};
/**
* @brief A list::const_iterator.
*
* All the functions are op overloads.
*/
template
struct _List_const_iterator
{
typedef const _List_node<_Tp> _Node;
typedef _List_iterator<_Tp> iterator;
typedef ptrdiff_t difference_type;
typedef std::bidirectional_iterator_tag iterator_category;
typedef _Tp value_type;
typedef const _Tp* pointer;
typedef const _Tp& reference;
_List_const_iterator() _GLIBCXX_NOEXCEPT
: _M_node() { }
explicit
_List_const_iterator(const __detail::_List_node_base* __x)
_GLIBCXX_NOEXCEPT
: _M_node(__x) { }
_List_const_iterator(const iterator& __x) _GLIBCXX_NOEXCEPT
: _M_node(__x._M_node) { }
iterator
_M_const_cast() const _GLIBCXX_NOEXCEPT
{ return iterator(const_cast<__detail::_List_node_base*>(_M_node)); }
// Must downcast from List_node_base to _List_node to get to value.
_GLIBCXX_NODISCARD
reference
operator*() const _GLIBCXX_NOEXCEPT
{ return *static_cast<_Node*>(_M_node)->_M_valptr(); }
_GLIBCXX_NODISCARD
pointer
operator->() const _GLIBCXX_NOEXCEPT
{ return static_cast<_Node*>(_M_node)->_M_valptr(); }
_List_const_iterator&
operator++() _GLIBCXX_NOEXCEPT
{
_M_node = _M_node->_M_next;
return *this;
}
_List_const_iterator
operator++(int) _GLIBCXX_NOEXCEPT
{
_List_const_iterator __tmp = *this;
_M_node = _M_node->_M_next;
return __tmp;
}
_List_const_iterator&
operator--() _GLIBCXX_NOEXCEPT
{
_M_node = _M_node->_M_prev;
return *this;
}
_List_const_iterator
operator--(int) _GLIBCXX_NOEXCEPT
{
_List_const_iterator __tmp = *this;
_M_node = _M_node->_M_prev;
return __tmp;
}
_GLIBCXX_NODISCARD
friend bool
operator==(const _List_const_iterator& __x,
const _List_const_iterator& __y) _GLIBCXX_NOEXCEPT
{ return __x._M_node == __y._M_node; }
#if __cpp_impl_three_way_comparison < 201907L
_GLIBCXX_NODISCARD
friend bool
operator!=(const _List_const_iterator& __x,
const _List_const_iterator& __y) _GLIBCXX_NOEXCEPT
{ return __x._M_node != __y._M_node; }
#endif
// The only member points to the %list element.
const __detail::_List_node_base* _M_node;
};
_GLIBCXX_BEGIN_NAMESPACE_CXX11
/// See bits/stl_deque.h's _Deque_base for an explanation.
template
class _List_base
{
protected:
typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
rebind<_Tp>::other _Tp_alloc_type;
typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Tp_alloc_traits;
typedef __list::_Node_traits<_Tp, typename _Tp_alloc_traits::pointer>
_Node_traits;
typedef typename _Tp_alloc_traits::template
rebind::other _Node_alloc_type;
typedef __gnu_cxx::__alloc_traits<_Node_alloc_type> _Node_alloc_traits;
#if __cplusplus < 201103L || ! _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
typedef _List_node<_Tp>* _Node_ptr;
#else
using _Node_ptr = typename _Node_alloc_traits::pointer;
#endif
struct _List_impl
: public _Node_alloc_type
{
typename _Node_traits::_Node_header _M_node;
_List_impl() _GLIBCXX_NOEXCEPT_IF(
is_nothrow_default_constructible<_Node_alloc_type>::value)
: _Node_alloc_type()
{ }
_List_impl(const _Node_alloc_type& __a) _GLIBCXX_NOEXCEPT
: _Node_alloc_type(__a)
{ }
#if __cplusplus >= 201103L
_List_impl(_List_impl&&) = default;
_List_impl(_Node_alloc_type&& __a, _List_impl&& __x)
: _Node_alloc_type(std::move(__a)), _M_node(std::move(__x._M_node))
{ }
_List_impl(_Node_alloc_type&& __a) noexcept
: _Node_alloc_type(std::move(__a))
{ }
#endif
};
_List_impl _M_impl;
#if _GLIBCXX_USE_CXX11_ABI
size_t _M_get_size() const { return _M_impl._M_node._M_size; }
void _M_set_size(size_t __n) { _M_impl._M_node._M_size = __n; }
void _M_inc_size(size_t __n) { _M_impl._M_node._M_size += __n; }
void _M_dec_size(size_t __n) { _M_impl._M_node._M_size -= __n; }
#else
// dummy implementations used when the size is not stored
size_t _M_get_size() const { return 0; }
void _M_set_size(size_t) { }
void _M_inc_size(size_t) { }
void _M_dec_size(size_t) { }
#endif
typename _Node_alloc_traits::pointer
_M_get_node()
{ return _Node_alloc_traits::allocate(_M_impl, 1); }
void
_M_put_node(_Node_ptr __p) _GLIBCXX_NOEXCEPT
{
#if __cplusplus < 201103L || _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
_Node_alloc_traits::deallocate(_M_impl, __p, 1);
#else
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
using __alloc_pointer = typename _Node_alloc_traits::pointer;
if constexpr (is_same<_Node_ptr, __alloc_pointer>::value)
_Node_alloc_traits::deallocate(_M_impl, __p, 1);
else
{
// When not using the allocator's pointer type internally we must
// convert __p to __alloc_pointer so it can be deallocated.
auto __ap = pointer_traits<__alloc_pointer>::pointer_to(*__p);
_Node_alloc_traits::deallocate(_M_impl, __ap, 1);
}
#pragma GCC diagnostic pop
#endif
}
void
_M_destroy_node(_Node_ptr __p)
{
// Destroy the element
#if __cplusplus < 201103L
_Tp_alloc_type(_M_impl).destroy(__p->_M_valptr());
#else
_Node_alloc_traits::destroy(_M_impl, __p->_M_valptr());
// Only destroy the node if the pointers require it.
using _Node = typename _Node_traits::_Node;
using _Base_ptr = typename _Node_traits::_Node_base::_Base_ptr;
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
if constexpr (!is_trivially_destructible<_Base_ptr>::value)
__p->~_Node();
#pragma GCC diagnostic pop
#endif
this->_M_put_node(__p);
}
public:
typedef _Alloc allocator_type;
_Node_alloc_type&
_M_get_Node_allocator() _GLIBCXX_NOEXCEPT
{ return _M_impl; }
const _Node_alloc_type&
_M_get_Node_allocator() const _GLIBCXX_NOEXCEPT
{ return _M_impl; }
#if __cplusplus >= 201103L
_List_base() = default;
#else
_List_base() { }
#endif
_List_base(const _Node_alloc_type& __a) _GLIBCXX_NOEXCEPT
: _M_impl(__a)
{ }
#if __cplusplus >= 201103L
_List_base(_List_base&&) = default;
// Used when allocator is_always_equal.
_List_base(_Node_alloc_type&& __a, _List_base&& __x)
: _M_impl(std::move(__a), std::move(__x._M_impl))
{ }
// Used when allocator !is_always_equal.
_List_base(_Node_alloc_type&& __a)
: _M_impl(std::move(__a))
{ }
void
_M_move_nodes(_List_base&& __x)
{ _M_impl._M_node._M_move_nodes(std::move(__x._M_impl._M_node)); }
#endif
// This is what actually destroys the list.
~_List_base() _GLIBCXX_NOEXCEPT
{ _M_clear(); }
void
_M_clear() _GLIBCXX_NOEXCEPT;
void
_M_init() _GLIBCXX_NOEXCEPT
{ this->_M_impl._M_node._M_init(); }
#if !_GLIBCXX_INLINE_VERSION
// XXX GLIBCXX_ABI Deprecated
// These members are unused by std::list now, but we keep them here
// so that an explicit instantiation of std::list will define them.
// This ensures that explicit instantiations still define these symbols,
// so that explicit instantiation declarations of std::list that were
// compiled with old versions of GCC can still find these old symbols.
// Use 'if constexpr' so that the functions don't do anything for
// specializations using _Node_traits, because any
// old code referencing these symbols wasn't using the fancy-pointer
// specializations.
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
# if __cplusplus >= 201103L
_List_base(_List_base&& __x, _Node_alloc_type&& __a)
: _M_impl(std::move(__a))
{
#if _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
if constexpr (is_same::value)
#endif
if (__x._M_get_Node_allocator() == _M_get_Node_allocator())
_M_move_nodes(std::move(__x));
// else caller must move individual elements.
}
# endif
static size_t
_S_distance(const __detail::_List_node_base* __first,
const __detail::_List_node_base* __last)
{
#if _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
if constexpr (!is_same::value)
return 0;
else
#endif
{
size_t __n = 0;
while (__first != __last)
{
__first = __first->_M_next;
++__n;
}
return __n;
}
}
#if _GLIBCXX_USE_CXX11_ABI
size_t
_M_distance(const __detail::_List_node_base* __first,
const __detail::_List_node_base* __last) const
{ return _S_distance(__first, __last); }
// return the stored size
size_t _M_node_count() const { return _M_get_size(); }
#else
size_t _M_distance(const void*, const void*) const { return 0; }
// count the number of nodes
size_t _M_node_count() const
{
return _S_distance(_M_impl._M_node._M_next, _M_impl._M_node._M_base());
}
#endif
#pragma GCC diagnostic pop
#endif // ! INLINE_VERSION
};
/**
* @brief A standard container with linear time access to elements,
* and fixed time insertion/deletion at any point in the sequence.
*
* @ingroup sequences
*
* @tparam _Tp Type of element.
* @tparam _Alloc Allocator type, defaults to allocator<_Tp>.
*
* Meets the requirements of a container, a
* reversible container, and a
* sequence, including the
* optional sequence requirements with the
* %exception of @c at and @c operator[].
*
* This is a @e doubly @e linked %list. Traversal up and down the
* %list requires linear time, but adding and removing elements (or
* @e nodes) is done in constant time, regardless of where the
* change takes place. Unlike std::vector and std::deque,
* random-access iterators are not provided, so subscripting ( @c
* [] ) access is not allowed. For algorithms which only need
* sequential access, this lack makes no difference.
*
* Also unlike the other standard containers, std::list provides
* specialized algorithms %unique to linked lists, such as
* splicing, sorting, and in-place reversal.
*
* A couple points on memory allocation for list:
*
* First, we never actually allocate a Tp, we allocate
* List_node's and trust [20.1.5]/4 to DTRT. This is to ensure
* that after elements from %list are spliced into
* %list, destroying the memory of the second %list is a
* valid operation, i.e., Alloc1 giveth and Alloc2 taketh away.
*
* Second, a %list conceptually represented as
* @code
* A <---> B <---> C <---> D
* @endcode
* is actually circular; a link exists between A and D. The %list
* class holds (as its only data member) a private list::iterator
* pointing to @e D, not to @e A! To get to the head of the %list,
* we start at the tail and move forward by one. When this member
* iterator's next/previous pointers refer to itself, the %list is
* %empty.
*/
template >
class list : protected _List_base<_Tp, _Alloc>
{
#ifdef _GLIBCXX_CONCEPT_CHECKS
// concept requirements
typedef typename _Alloc::value_type _Alloc_value_type;
# if __cplusplus < 201103L
__glibcxx_class_requires(_Tp, _SGIAssignableConcept)
# endif
__glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept)
#endif
#if __cplusplus >= 201103L
static_assert(is_same::type, _Tp>::value,
"std::list must have a non-const, non-volatile value_type");
# if __cplusplus > 201703L || defined __STRICT_ANSI__
static_assert(is_same::value,
"std::list must have the same value_type as its allocator");
# endif
#endif
typedef _List_base<_Tp, _Alloc> _Base;
typedef typename _Base::_Tp_alloc_type _Tp_alloc_type;
typedef typename _Base::_Tp_alloc_traits _Tp_alloc_traits;
typedef typename _Base::_Node_alloc_type _Node_alloc_type;
typedef typename _Base::_Node_alloc_traits _Node_alloc_traits;
typedef typename _Base::_Node_traits _Node_traits;
public:
typedef _Tp value_type;
typedef typename _Tp_alloc_traits::pointer pointer;
typedef typename _Tp_alloc_traits::const_pointer const_pointer;
typedef typename _Tp_alloc_traits::reference reference;
typedef typename _Tp_alloc_traits::const_reference const_reference;
typedef typename _Node_traits::_Iterator iterator;
typedef typename _Node_traits::_Const_iterator const_iterator;
typedef std::reverse_iterator const_reverse_iterator;
typedef std::reverse_iterator reverse_iterator;
typedef size_t size_type;
typedef ptrdiff_t difference_type;
typedef _Alloc allocator_type;
protected:
// Note that pointers-to-_Node's can be ctor-converted to
// iterator types.
typedef typename _Node_alloc_traits::pointer _Node_ptr;
using _Base::_M_impl;
using _Base::_M_put_node;
using _Base::_M_get_node;
using _Base::_M_get_Node_allocator;
/**
* @param __args An instance of user data.
*
* Allocates space for a new node and constructs a copy of
* @a __args in it.
*/
#if __cplusplus < 201103L
_Node_ptr
_M_create_node(const value_type& __x)
{
_Node_ptr __p = this->_M_get_node();
__try
{
_Tp_alloc_type __alloc(_M_get_Node_allocator());
__alloc.construct(__p->_M_valptr(), __x);
}
__catch(...)
{
_M_put_node(__p);
__throw_exception_again;
}
return __p;
}
#else
template
_Node_ptr
_M_create_node(_Args&&... __args)
{
auto& __alloc = _M_get_Node_allocator();
auto __guard = std::__allocate_guarded_obj(__alloc);
_Node_alloc_traits::construct(__alloc, __guard->_M_valptr(),
std::forward<_Args>(__args)...);
return __guard.release();
}
#endif
public:
// [23.2.2.1] construct/copy/destroy
// (assign() and get_allocator() are also listed in this section)
/**
* @brief Creates a %list with no elements.
*/
#if __cplusplus >= 201103L
list() = default;
#else
list() { }
#endif
/**
* @brief Creates a %list with no elements.
* @param __a An allocator object.
*/
explicit
list(const allocator_type& __a) _GLIBCXX_NOEXCEPT
: _Base(_Node_alloc_type(__a)) { }
#if __cplusplus >= 201103L
/**
* @brief Creates a %list with default constructed elements.
* @param __n The number of elements to initially create.
* @param __a An allocator object.
*
* This constructor fills the %list with @a __n default
* constructed elements.
*/
explicit
list(size_type __n, const allocator_type& __a = allocator_type())
: _Base(_Node_alloc_type(__a))
{ _M_default_initialize(__n); }
/**
* @brief Creates a %list with copies of an exemplar element.
* @param __n The number of elements to initially create.
* @param __value An element to copy.
* @param __a An allocator object.
*
* This constructor fills the %list with @a __n copies of @a __value.
*/
list(size_type __n, const value_type& __value,
const allocator_type& __a = allocator_type())
: _Base(_Node_alloc_type(__a))
{ _M_fill_initialize(__n, __value); }
#else
/**
* @brief Creates a %list with copies of an exemplar element.
* @param __n The number of elements to initially create.
* @param __value An element to copy.
* @param __a An allocator object.
*
* This constructor fills the %list with @a __n copies of @a __value.
*/
explicit
list(size_type __n, const value_type& __value = value_type(),
const allocator_type& __a = allocator_type())
: _Base(_Node_alloc_type(__a))
{ _M_fill_initialize(__n, __value); }
#endif
/**
* @brief %List copy constructor.
* @param __x A %list of identical element and allocator types.
*
* The newly-created %list uses a copy of the allocation object used
* by @a __x (unless the allocator traits dictate a different object).
*/
list(const list& __x)
: _Base(_Node_alloc_traits::
_S_select_on_copy(__x._M_get_Node_allocator()))
{ _M_initialize_dispatch(__x.begin(), __x.end(), __false_type()); }
#if __cplusplus >= 201103L
/**
* @brief %List move constructor.
*
* The newly-created %list contains the exact contents of the moved
* instance. The contents of the moved instance are a valid, but
* unspecified %list.
*/
list(list&&) = default;
/**
* @brief Builds a %list from an initializer_list
* @param __l An initializer_list of value_type.
* @param __a An allocator object.
*
* Create a %list consisting of copies of the elements in the
* initializer_list @a __l. This is linear in __l.size().
*/
list(initializer_list __l,
const allocator_type& __a = allocator_type())
: _Base(_Node_alloc_type(__a))
{ _M_initialize_dispatch(__l.begin(), __l.end(), __false_type()); }
list(const list& __x, const __type_identity_t& __a)
: _Base(_Node_alloc_type(__a))
{ _M_initialize_dispatch(__x.begin(), __x.end(), __false_type()); }
private:
list(list&& __x, const allocator_type& __a, true_type) noexcept
: _Base(_Node_alloc_type(__a), std::move(__x))
{ }
list(list&& __x, const allocator_type& __a, false_type)
: _Base(_Node_alloc_type(__a))
{
if (__x._M_get_Node_allocator() == this->_M_get_Node_allocator())
this->_M_move_nodes(std::move(__x));
else
insert(begin(), std::__make_move_if_noexcept_iterator(__x.begin()),
std::__make_move_if_noexcept_iterator(__x.end()));
}
public:
list(list&& __x, const __type_identity_t& __a)
noexcept(_Node_alloc_traits::_S_always_equal())
: list(std::move(__x), __a,
typename _Node_alloc_traits::is_always_equal{})
{ }
#endif
/**
* @brief Builds a %list from a range.
* @param __first An input iterator.
* @param __last An input iterator.
* @param __a An allocator object.
*
* Create a %list consisting of copies of the elements from
* [@a __first,@a __last). This is linear in N (where N is
* distance(@a __first,@a __last)).
*/
#if __cplusplus >= 201103L
template>
list(_InputIterator __first, _InputIterator __last,
const allocator_type& __a = allocator_type())
: _Base(_Node_alloc_type(__a))
{ _M_initialize_dispatch(__first, __last, __false_type()); }
#else
template
list(_InputIterator __first, _InputIterator __last,
const allocator_type& __a = allocator_type())
: _Base(_Node_alloc_type(__a))
{
// Check whether it's an integral type. If so, it's not an iterator.
typedef typename std::__is_integer<_InputIterator>::__type _Integral;
_M_initialize_dispatch(__first, __last, _Integral());
}
#endif
#if __glibcxx_containers_ranges // C++ >= 23
/**
* @brief Construct a list from a range.
* @since C++23
*/
template<__detail::__container_compatible_range<_Tp> _Rg>
list(from_range_t, _Rg&& __rg, const _Alloc& __a = _Alloc())
: _Base(_Node_alloc_type(__a))
{
auto __first = ranges::begin(__rg);
const auto __last = ranges::end(__rg);
for (; __first != __last; ++__first)
emplace_back(*__first);
}
#endif
#if __cplusplus >= 201103L
/**
* No explicit dtor needed as the _Base dtor takes care of
* things. The _Base dtor only erases the elements, and note
* that if the elements themselves are pointers, the pointed-to
* memory is not touched in any way. Managing the pointer is
* the user's responsibility.
*/
~list() = default;
#endif
/**
* @brief %List assignment operator.
* @param __x A %list of identical element and allocator types.
*
* All the elements of @a __x are copied.
*
* Whether the allocator is copied depends on the allocator traits.
*/
list&
operator=(const list& __x);
#if __cplusplus >= 201103L
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
/**
* @brief %List move assignment operator.
* @param __x A %list of identical element and allocator types.
*
* The contents of @a __x are moved into this %list (without copying).
*
* Afterwards @a __x is a valid, but unspecified %list
*
* Whether the allocator is moved depends on the allocator traits.
*/
list&
operator=(list&& __x)
noexcept(_Node_alloc_traits::_S_nothrow_move())
{
constexpr bool __move_storage =
_Node_alloc_traits::_S_propagate_on_move_assign()
|| _Node_alloc_traits::_S_always_equal();
if constexpr (!__move_storage)
{
if (__x._M_get_Node_allocator() != this->_M_get_Node_allocator())
{
// The rvalue's allocator cannot be moved, or is not equal,
// so we need to individually move each element.
_M_assign_dispatch(std::make_move_iterator(__x.begin()),
std::make_move_iterator(__x.end()),
__false_type{});
return *this;
}
}
this->clear();
this->_M_move_nodes(std::move(__x));
if constexpr (_Node_alloc_traits::_S_propagate_on_move_assign())
this->_M_get_Node_allocator()
= std::move(__x._M_get_Node_allocator());
return *this;
}
#pragma GCC diagnostic pop
/**
* @brief %List initializer list assignment operator.
* @param __l An initializer_list of value_type.
*
* Replace the contents of the %list with copies of the elements
* in the initializer_list @a __l. This is linear in l.size().
*/
list&
operator=(initializer_list __l)
{
this->assign(__l.begin(), __l.end());
return *this;
}
#endif
#if __glibcxx_containers_ranges // C++ >= 23
/**
* @brief Assign a range to a list.
* @since C++23
*/
template<__detail::__container_compatible_range<_Tp> _Rg>
void
assign_range(_Rg&& __rg)
{
static_assert(assignable_from<_Tp&, ranges::range_reference_t<_Rg>>);
iterator __first1 = begin();
const iterator __last1 = end();
auto __first2 = ranges::begin(__rg);
const auto __last2 = ranges::end(__rg);
for (; __first1 != __last1 && __first2 != __last2;
++__first1, (void)++__first2)
*__first1 = *__first2;
if (__first2 == __last2)
erase(__first1, __last1);
else
insert_range(__last1,
ranges::subrange(std::move(__first2), __last2));
}
#endif
/**
* @brief Assigns a given value to a %list.
* @param __n Number of elements to be assigned.
* @param __val Value to be assigned.
*
* This function fills a %list with @a __n copies of the given
* value. Note that the assignment completely changes the %list
* and that the resulting %list's size is the same as the number
* of elements assigned.
*/
void
assign(size_type __n, const value_type& __val)
{ _M_fill_assign(__n, __val); }
/**
* @brief Assigns a range to a %list.
* @param __first An input iterator.
* @param __last An input iterator.
*
* This function fills a %list with copies of the elements in the
* range [@a __first,@a __last).
*
* Note that the assignment completely changes the %list and
* that the resulting %list's size is the same as the number of
* elements assigned.
*/
#if __cplusplus >= 201103L
template>
void
assign(_InputIterator __first, _InputIterator __last)
{ _M_assign_dispatch(__first, __last, __false_type()); }
#else
template
void
assign(_InputIterator __first, _InputIterator __last)
{
// Check whether it's an integral type. If so, it's not an iterator.
typedef typename std::__is_integer<_InputIterator>::__type _Integral;
_M_assign_dispatch(__first, __last, _Integral());
}
#endif
#if __cplusplus >= 201103L
/**
* @brief Assigns an initializer_list to a %list.
* @param __l An initializer_list of value_type.
*
* Replace the contents of the %list with copies of the elements
* in the initializer_list @a __l. This is linear in __l.size().
*/
void
assign(initializer_list __l)
{ this->_M_assign_dispatch(__l.begin(), __l.end(), __false_type()); }
#endif
/// Get a copy of the memory allocation object.
allocator_type
get_allocator() const _GLIBCXX_NOEXCEPT
{ return allocator_type(_Base::_M_get_Node_allocator()); }
// iterators
/**
* Returns a read/write iterator that points to the first element in the
* %list. Iteration is done in ordinary element order.
*/
_GLIBCXX_NODISCARD
iterator
begin() _GLIBCXX_NOEXCEPT
{ return iterator(this->_M_impl._M_node._M_next); }
/**
* Returns a read-only (constant) iterator that points to the
* first element in the %list. Iteration is done in ordinary
* element order.
*/
_GLIBCXX_NODISCARD
const_iterator
begin() const _GLIBCXX_NOEXCEPT
{ return const_iterator(this->_M_impl._M_node._M_next); }
/**
* Returns a read/write iterator that points one past the last
* element in the %list. Iteration is done in ordinary element
* order.
*/
_GLIBCXX_NODISCARD
iterator
end() _GLIBCXX_NOEXCEPT
{ return iterator(this->_M_impl._M_node._M_base()); }
/**
* Returns a read-only (constant) iterator that points one past
* the last element in the %list. Iteration is done in ordinary
* element order.
*/
_GLIBCXX_NODISCARD
const_iterator
end() const _GLIBCXX_NOEXCEPT
{ return const_iterator(this->_M_impl._M_node._M_base()); }
/**
* Returns a read/write reverse iterator that points to the last
* element in the %list. Iteration is done in reverse element
* order.
*/
_GLIBCXX_NODISCARD
reverse_iterator
rbegin() _GLIBCXX_NOEXCEPT
{ return reverse_iterator(end()); }
/**
* Returns a read-only (constant) reverse iterator that points to
* the last element in the %list. Iteration is done in reverse
* element order.
*/
_GLIBCXX_NODISCARD
const_reverse_iterator
rbegin() const _GLIBCXX_NOEXCEPT
{ return const_reverse_iterator(end()); }
/**
* Returns a read/write reverse iterator that points to one
* before the first element in the %list. Iteration is done in
* reverse element order.
*/
_GLIBCXX_NODISCARD
reverse_iterator
rend() _GLIBCXX_NOEXCEPT
{ return reverse_iterator(begin()); }
/**
* Returns a read-only (constant) reverse iterator that points to one
* before the first element in the %list. Iteration is done in reverse
* element order.
*/
_GLIBCXX_NODISCARD
const_reverse_iterator
rend() const _GLIBCXX_NOEXCEPT
{ return const_reverse_iterator(begin()); }
#if __cplusplus >= 201103L
/**
* Returns a read-only (constant) iterator that points to the
* first element in the %list. Iteration is done in ordinary
* element order.
*/
[[__nodiscard__]]
const_iterator
cbegin() const noexcept
{ return const_iterator(this->_M_impl._M_node._M_next); }
/**
* Returns a read-only (constant) iterator that points one past
* the last element in the %list. Iteration is done in ordinary
* element order.
*/
[[__nodiscard__]]
const_iterator
cend() const noexcept
{ return const_iterator(this->_M_impl._M_node._M_base()); }
/**
* Returns a read-only (constant) reverse iterator that points to
* the last element in the %list. Iteration is done in reverse
* element order.
*/
[[__nodiscard__]]
const_reverse_iterator
crbegin() const noexcept
{ return const_reverse_iterator(end()); }
/**
* Returns a read-only (constant) reverse iterator that points to one
* before the first element in the %list. Iteration is done in reverse
* element order.
*/
[[__nodiscard__]]
const_reverse_iterator
crend() const noexcept
{ return const_reverse_iterator(begin()); }
#endif
// [23.2.2.2] capacity
/**
* Returns true if the %list is empty. (Thus begin() would equal
* end().)
*/
_GLIBCXX_NODISCARD bool
empty() const _GLIBCXX_NOEXCEPT
{
return this->_M_impl._M_node._M_next == this->_M_impl._M_node._M_base();
}
/** Returns the number of elements in the %list. */
_GLIBCXX_NODISCARD
size_type
size() const _GLIBCXX_NOEXCEPT
{
#if _GLIBCXX_USE_CXX11_ABI
return this->_M_get_size(); // return the stored size
#else
return std::distance(begin(), end()); // count the number of nodes
#endif
}
/** Returns the size() of the largest possible %list. */
_GLIBCXX_NODISCARD
size_type
max_size() const _GLIBCXX_NOEXCEPT
{ return _Node_alloc_traits::max_size(_M_get_Node_allocator()); }
#if __cplusplus >= 201103L
/**
* @brief Resizes the %list to the specified number of elements.
* @param __new_size Number of elements the %list should contain.
*
* This function will %resize the %list to the specified number
* of elements. If the number is smaller than the %list's
* current size the %list is truncated, otherwise default
* constructed elements are appended.
*/
void
resize(size_type __new_size);
/**
* @brief Resizes the %list to the specified number of elements.
* @param __new_size Number of elements the %list should contain.
* @param __x Data with which new elements should be populated.
*
* This function will %resize the %list to the specified number
* of elements. If the number is smaller than the %list's
* current size the %list is truncated, otherwise the %list is
* extended and new elements are populated with given data.
*/
void
resize(size_type __new_size, const value_type& __x);
#else
/**
* @brief Resizes the %list to the specified number of elements.
* @param __new_size Number of elements the %list should contain.
* @param __x Data with which new elements should be populated.
*
* This function will %resize the %list to the specified number
* of elements. If the number is smaller than the %list's
* current size the %list is truncated, otherwise the %list is
* extended and new elements are populated with given data.
*/
void
resize(size_type __new_size, value_type __x = value_type());
#endif
// element access
/**
* Returns a read/write reference to the data at the first
* element of the %list.
*/
_GLIBCXX_NODISCARD
reference
front() _GLIBCXX_NOEXCEPT
{
__glibcxx_requires_nonempty();
return *begin();
}
/**
* Returns a read-only (constant) reference to the data at the first
* element of the %list.
*/
_GLIBCXX_NODISCARD
const_reference
front() const _GLIBCXX_NOEXCEPT
{
__glibcxx_requires_nonempty();
return *begin();
}
/**
* Returns a read/write reference to the data at the last element
* of the %list.
*/
_GLIBCXX_NODISCARD
reference
back() _GLIBCXX_NOEXCEPT
{
__glibcxx_requires_nonempty();
iterator __tmp = end();
--__tmp;
return *__tmp;
}
/**
* Returns a read-only (constant) reference to the data at the last
* element of the %list.
*/
_GLIBCXX_NODISCARD
const_reference
back() const _GLIBCXX_NOEXCEPT
{
__glibcxx_requires_nonempty();
const_iterator __tmp = end();
--__tmp;
return *__tmp;
}
// [23.2.2.3] modifiers
/**
* @brief Add data to the front of the %list.
* @param __x Data to be added.
*
* This is a typical stack operation. The function creates an
* element at the front of the %list and assigns the given data
* to it. Due to the nature of a %list this operation can be
* done in constant time, and does not invalidate iterators and
* references.
*/
void
push_front(const value_type& __x)
{ this->_M_insert(begin(), __x); }
#if __cplusplus >= 201103L
void
push_front(value_type&& __x)
{ this->_M_insert(begin(), std::move(__x)); }
template
#if __cplusplus > 201402L
reference
#else
void
#endif
emplace_front(_Args&&... __args)
{
this->_M_insert(begin(), std::forward<_Args>(__args)...);
#if __cplusplus > 201402L
return front();
#endif
}
#endif
#if __glibcxx_containers_ranges // C++ >= 23
/**
* @brief Insert a range at the beginning of a list.
* @param __rg An input range of elements that can be converted to
* the list's value type.
*
* Inserts the elements of `__rg` at the beginning of the list.
* No iterators to existing elements are invalidated by this function.
* If the insertion fails due to an exception, no elements will be added
* and so the list will be unchanged.
*
* @since C++23
*/
template<__detail::__container_compatible_range<_Tp> _Rg>
void
prepend_range(_Rg&& __rg)
{
list __tmp(from_range, std::forward<_Rg>(__rg), get_allocator());
if (!__tmp.empty())
splice(begin(), __tmp);
}
/**
* @brief Insert a range at the end of a list.
* @param __rg An input range of elements that can be converted to
* the list's value type.
*
* Inserts the elements of `__rg` at the end of the list.
* No iterators to existing elements are invalidated by this function.
* If the insertion fails due to an exception, no elements will be added
* and so the list will be unchanged.
*
* @since C++23
*/
template<__detail::__container_compatible_range<_Tp> _Rg>
void
append_range(_Rg&& __rg)
{
list __tmp(from_range, std::forward<_Rg>(__rg), get_allocator());
if (!__tmp.empty())
splice(end(), __tmp);
}
#endif
/**
* @brief Removes first element.
*
* This is a typical stack operation. It shrinks the %list by
* one. Due to the nature of a %list this operation can be done
* in constant time, and only invalidates iterators/references to
* the element being removed.
*
* Note that no data is returned, and if the first element's data
* is needed, it should be retrieved before pop_front() is
* called.
*/
void
pop_front() _GLIBCXX_NOEXCEPT
{
__glibcxx_requires_nonempty();
this->_M_erase(begin());
}
/**
* @brief Add data to the end of the %list.
* @param __x Data to be added.
*
* This is a typical stack operation. The function creates an
* element at the end of the %list and assigns the given data to
* it. Due to the nature of a %list this operation can be done
* in constant time, and does not invalidate iterators and
* references.
*/
void
push_back(const value_type& __x)
{ this->_M_insert(end(), __x); }
#if __cplusplus >= 201103L
void
push_back(value_type&& __x)
{ this->_M_insert(end(), std::move(__x)); }
template
#if __cplusplus > 201402L
reference
#else
void
#endif
emplace_back(_Args&&... __args)
{
this->_M_insert(end(), std::forward<_Args>(__args)...);
#if __cplusplus > 201402L
return back();
#endif
}
#endif
/**
* @brief Removes last element.
*
* This is a typical stack operation. It shrinks the %list by
* one. Due to the nature of a %list this operation can be done
* in constant time, and only invalidates iterators/references to
* the element being removed.
*
* Note that no data is returned, and if the last element's data
* is needed, it should be retrieved before pop_back() is called.
*/
void
pop_back() _GLIBCXX_NOEXCEPT
{
__glibcxx_requires_nonempty();
this->_M_erase(iterator(this->_M_impl._M_node._M_prev));
}
#if __cplusplus >= 201103L
/**
* @brief Constructs object in %list before specified iterator.
* @param __position A const_iterator into the %list.
* @param __args Arguments.
* @return An iterator that points to the inserted data.
*
* This function will insert an object of type T constructed
* with T(std::forward(args)...) before the specified
* location. Due to the nature of a %list this operation can
* be done in constant time, and does not invalidate iterators
* and references.
*/
template
iterator
emplace(const_iterator __position, _Args&&... __args);
#endif
/**
* @brief Inserts given value into %list before specified iterator.
* @param __position An iterator into the %list.
* @param __x Data to be inserted.
* @return An iterator that points to the inserted data.
*
* This function will insert a copy of the given value before
* the specified location. Due to the nature of a %list this
* operation can be done in constant time, and does not
* invalidate iterators and references.
*
* @{
*/
#if __cplusplus >= 201103L
iterator
insert(const_iterator __position, const value_type& __x);
iterator
insert(const_iterator __position, value_type&& __x)
{ return emplace(__position, std::move(__x)); }
#else
iterator
insert(iterator __position, const value_type& __x);
#endif
/// @}
#if __cplusplus >= 201103L
/**
* @brief Inserts the contents of an initializer_list into %list
* before specified const_iterator.
* @param __p A const_iterator into the %list.
* @param __l An initializer_list of value_type.
* @return An iterator pointing to the first element inserted
* (or `__p`).
*
* This function will insert copies of the data in the
* initializer_list `__l` into the %list before the location
* specified by `__p`.
*
* This operation is linear in the number of elements inserted and
* does not invalidate iterators and references.
*/
iterator
insert(const_iterator __p, initializer_list __l)
{ return this->insert(__p, __l.begin(), __l.end()); }
#endif
/**
* @brief Inserts a number of copies of given data into the %list.
* @param __position An iterator into the %list.
* @param __n Number of elements to be inserted.
* @param __x Data to be inserted.
* @return Since C++11, an iterator pointing to the first element
* inserted (or `__position`). In C++98 this returns void.
*
* This function will insert a specified number of copies of the
* given data before the location specified by `__position`.
*
* This operation is linear in the number of elements inserted and
* does not invalidate iterators and references.
*/
#if __cplusplus >= 201103L
iterator
insert(const_iterator __position, size_type __n, const value_type& __x);
#else
void
insert(iterator __position, size_type __n, const value_type& __x)
{
list __tmp(__n, __x, get_allocator());
splice(__position, __tmp);
}
#endif
/**
* @brief Inserts a range into the %list.
* @param __position An iterator into the %list.
* @param __first An input iterator.
* @param __last An input iterator.
* @return Since C++11, an iterator pointing to the first element
* inserted (or `__position`). In C++98 this returns void.
*
* This function will insert copies of the data in the range
* `[__first,__last)` into the %list before the location specified by
* `__position`.
*
* This operation is linear in the number of elements inserted and
* does not invalidate iterators and references.
*/
#if __cplusplus >= 201103L
template>
iterator
insert(const_iterator __position, _InputIterator __first,
_InputIterator __last);
#else
template
void
insert(iterator __position, _InputIterator __first,
_InputIterator __last)
{
list __tmp(__first, __last, get_allocator());
splice(__position, __tmp);
}
#endif
#if __glibcxx_containers_ranges // C++ >= 23
/**
* @brief Insert a range into a list.
* @param __position An iterator.
* @param __rg An input range of elements that can be converted to
* the list's value type.
* @return An iterator pointing to the first element inserted,
* or `__position` if the range is empty.
*
* Inserts the elements of `__rg` before `__position`.
* No iterators to existing elements are invalidated by this function.
* If the insertion fails due to an exception, no elements will be added
* and so the list will be unchanged.
*
* @since C++23
*/
template<__detail::__container_compatible_range<_Tp> _Rg>
iterator
insert_range(const_iterator __position, _Rg&& __rg)
{
list __tmp(from_range, std::forward<_Rg>(__rg), get_allocator());
if (!__tmp.empty())
{
auto __it = __tmp.begin();
splice(__position, __tmp);
return __it;
}
return __position._M_const_cast();
}
#endif
/**
* @brief Remove element at given position.
* @param __position Iterator pointing to element to be erased.
* @return An iterator pointing to the next element (or end()).
*
* This function will erase the element at the given position and thus
* shorten the %list by one.
*
* Due to the nature of a %list this operation can be done in
* constant time, and only invalidates iterators/references to
* the element being removed. The user is also cautioned that
* this function only erases the element, and that if the element
* is itself a pointer, the pointed-to memory is not touched in
* any way. Managing the pointer is the user's responsibility.
*/
iterator
#if __cplusplus >= 201103L
erase(const_iterator __position) noexcept;
#else
erase(iterator __position);
#endif
/**
* @brief Remove a range of elements.
* @param __first Iterator pointing to the first element to be erased.
* @param __last Iterator pointing to one past the last element to be
* erased.
* @return An iterator pointing to the element pointed to by @a last
* prior to erasing (or end()).
*
* This function will erase the elements in the range @a
* [first,last) and shorten the %list accordingly.
*
* This operation is linear time in the size of the range and only
* invalidates iterators/references to the element being removed.
* The user is also cautioned that this function only erases the
* elements, and that if the elements themselves are pointers, the
* pointed-to memory is not touched in any way. Managing the pointer
* is the user's responsibility.
*/
iterator
#if __cplusplus >= 201103L
erase(const_iterator __first, const_iterator __last) noexcept
#else
erase(iterator __first, iterator __last)
#endif
{
while (__first != __last)
__first = erase(__first);
return __last._M_const_cast();
}
/**
* @brief Swaps data with another %list.
* @param __x A %list of the same element and allocator types.
*
* This exchanges the elements between two lists in constant
* time. Note that the global std::swap() function is
* specialized such that std::swap(l1,l2) will feed to this
* function.
*
* Whether the allocators are swapped depends on the allocator traits.
*/
void
swap(list& __x) _GLIBCXX_NOEXCEPT
{
_Node_traits::_Node_base::swap(this->_M_impl._M_node,
__x._M_impl._M_node);
size_t __xsize = __x._M_get_size();
__x._M_set_size(this->_M_get_size());
this->_M_set_size(__xsize);
_Node_alloc_traits::_S_on_swap(this->_M_get_Node_allocator(),
__x._M_get_Node_allocator());
}
/**
* Erases all the elements. Note that this function only erases
* the elements, and that if the elements themselves are
* pointers, the pointed-to memory is not touched in any way.
* Managing the pointer is the user's responsibility.
*/
void
clear() _GLIBCXX_NOEXCEPT
{
_Base::_M_clear();
_Base::_M_init();
}
// [23.2.2.4] list operations
/**
* @brief Insert contents of another %list.
* @param __position Iterator referencing the element to insert before.
* @param __x Source list.
*
* The elements of @a __x are inserted in constant time in front of
* the element referenced by @a __position. @a __x becomes an empty
* list.
*
* Requires this != @a __x.
*/
void
#if __cplusplus >= 201103L
splice(const_iterator __position, list&& __x) noexcept
#else
splice(iterator __position, list& __x)
#endif
{
if (!__x.empty())
{
_M_check_equal_allocators(__x);
this->_M_transfer(__position._M_const_cast(),
__x.begin(), __x.end());
this->_M_inc_size(__x._M_get_size());
__x._M_set_size(0);
}
}
#if __cplusplus >= 201103L
void
splice(const_iterator __position, list& __x) noexcept
{ splice(__position, std::move(__x)); }
#endif
/**
* @brief Insert element from another %list.
* @param __position Iterator referencing the element to insert before.
* @param __x Source list.
* @param __i Iterator referencing the element to move.
*
* Removes the element in list @a __x referenced by @a __i and
* inserts it into the current list before @a __position.
*
* @{
*/
#if __cplusplus >= 201103L
void
splice(const_iterator __position, list&& __x, const_iterator __i) noexcept
#else
void
splice(iterator __position, list& __x, iterator __i)
#endif
{
iterator __j = __i._M_const_cast();
++__j;
if (__position == __i || __position == __j)
return;
if (this != std::__addressof(__x))
_M_check_equal_allocators(__x);
this->_M_transfer(__position._M_const_cast(),
__i._M_const_cast(), __j);
this->_M_inc_size(1);
__x._M_dec_size(1);
}
#if __cplusplus >= 201103L
void
splice(const_iterator __position, list& __x, const_iterator __i) noexcept
{ splice(__position, std::move(__x), __i); }
#endif
/// @}
/**
* @brief Insert range from another %list.
* @param __position Iterator referencing the element to insert before.
* @param __x Source list.
* @param __first Iterator referencing the start of range in x.
* @param __last Iterator referencing the end of range in x.
*
* Removes elements in the range [__first,__last) and inserts them
* before @a __position in constant time.
*
* Undefined if @a __position is in [__first,__last).
*/
#if __cplusplus >= 201103L
void
splice(const_iterator __position, list&& __x, const_iterator __first,
const_iterator __last) noexcept
#else
void
splice(iterator __position, list& __x, iterator __first,
iterator __last)
#endif
{
if (__first != __last)
{
if (this != std::__addressof(__x))
_M_check_equal_allocators(__x);
#if _GLIBCXX_USE_CXX11_ABI
size_t __n = std::distance(__first, __last);
this->_M_inc_size(__n);
__x._M_dec_size(__n);
#endif
this->_M_transfer(__position._M_const_cast(),
__first._M_const_cast(),
__last._M_const_cast());
}
}
#if __cplusplus >= 201103L
/**
* @brief Insert range from another %list.
* @param __position Const_iterator referencing the element to
* insert before.
* @param __x Source list.
* @param __first Const_iterator referencing the start of range in x.
* @param __last Const_iterator referencing the end of range in x.
*
* Removes elements in the range [__first,__last) and inserts them
* before @a __position in constant time.
*
* Undefined if @a __position is in [__first,__last).
*/
void
splice(const_iterator __position, list& __x, const_iterator __first,
const_iterator __last) noexcept
{ splice(__position, std::move(__x), __first, __last); }
#endif
private:
#ifdef __glibcxx_list_remove_return_type // C++ >= 20 && HOSTED
typedef size_type __remove_return_type;
# define _GLIBCXX_LIST_REMOVE_RETURN_TYPE_TAG \
__attribute__((__abi_tag__("__cxx20")))
#else
typedef void __remove_return_type;
# define _GLIBCXX_LIST_REMOVE_RETURN_TYPE_TAG
#endif
public:
/**
* @brief Remove all elements equal to value.
* @param __value The value to remove.
*
* Removes every element in the list equal to @a value.
* Remaining elements stay in list order. Note that this
* function only erases the elements, and that if the elements
* themselves are pointers, the pointed-to memory is not
* touched in any way. Managing the pointer is the user's
* responsibility.
*/
_GLIBCXX_LIST_REMOVE_RETURN_TYPE_TAG
__remove_return_type
remove(const _Tp& __value);
/**
* @brief Remove all elements satisfying a predicate.
* @tparam _Predicate Unary predicate function or object.
*
* Removes every element in the list for which the predicate
* returns true. Remaining elements stay in list order. Note
* that this function only erases the elements, and that if the
* elements themselves are pointers, the pointed-to memory is
* not touched in any way. Managing the pointer is the user's
* responsibility.
*/
template
__remove_return_type
remove_if(_Predicate);
/**
* @brief Remove consecutive duplicate elements.
*
* For each consecutive set of elements with the same value,
* remove all but the first one. Remaining elements stay in
* list order. Note that this function only erases the
* elements, and that if the elements themselves are pointers,
* the pointed-to memory is not touched in any way. Managing
* the pointer is the user's responsibility.
*/
_GLIBCXX_LIST_REMOVE_RETURN_TYPE_TAG
__remove_return_type
unique();
/**
* @brief Remove consecutive elements satisfying a predicate.
* @tparam _BinaryPredicate Binary predicate function or object.
*
* For each consecutive set of elements [first,last) that
* satisfy predicate(first,i) where i is an iterator in
* [first,last), remove all but the first one. Remaining
* elements stay in list order. Note that this function only
* erases the elements, and that if the elements themselves are
* pointers, the pointed-to memory is not touched in any way.
* Managing the pointer is the user's responsibility.
*/
template
__remove_return_type
unique(_BinaryPredicate);
#undef _GLIBCXX_LIST_REMOVE_RETURN_TYPE_TAG
/**
* @brief Merge sorted lists.
* @param __x Sorted list to merge.
*
* Assumes that both @a __x and this list are sorted according to
* operator<(). Merges elements of @a __x into this list in
* sorted order, leaving @a __x empty when complete. Elements in
* this list precede elements in @a __x that are equal.
*/
#if __cplusplus >= 201103L
void
merge(list&& __x);
void
merge(list& __x)
{ merge(std::move(__x)); }
#else
void
merge(list& __x);
#endif
/**
* @brief Merge sorted lists according to comparison function.
* @tparam _StrictWeakOrdering Comparison function defining
* sort order.
* @param __x Sorted list to merge.
* @param __comp Comparison functor.
*
* Assumes that both @a __x and this list are sorted according to
* StrictWeakOrdering. Merges elements of @a __x into this list
* in sorted order, leaving @a __x empty when complete. Elements
* in this list precede elements in @a __x that are equivalent
* according to StrictWeakOrdering().
*/
#if __cplusplus >= 201103L
template
void
merge(list&& __x, _StrictWeakOrdering __comp);
template
void
merge(list& __x, _StrictWeakOrdering __comp)
{ merge(std::move(__x), __comp); }
#else
template
void
merge(list& __x, _StrictWeakOrdering __comp);
#endif
/**
* @brief Reverse the elements in list.
*
* Reverse the order of elements in the list in linear time.
*/
void
reverse() _GLIBCXX_NOEXCEPT
{ this->_M_impl._M_node._M_reverse(); }
/**
* @brief Sort the elements.
*
* Sorts the elements of this list in NlogN time. Equivalent
* elements remain in list order.
*/
void
sort();
/**
* @brief Sort the elements according to comparison function.
*
* Sorts the elements of this list in NlogN time. Equivalent
* elements remain in list order.
*/
template
void
sort(_StrictWeakOrdering);
protected:
// Internal constructor functions follow.
// Called by the range constructor to implement [23.1.1]/9
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 438. Ambiguity in the "do the right thing" clause
template
void
_M_initialize_dispatch(_Integer __n, _Integer __x, __true_type)
{ _M_fill_initialize(static_cast(__n), __x); }
// Called by the range constructor to implement [23.1.1]/9
template
void
_M_initialize_dispatch(_InputIterator __first, _InputIterator __last,
__false_type)
{
bool __notempty = __first != __last;
for (; __first != __last; ++__first)
#if __cplusplus >= 201103L
emplace_back(*__first);
#else
push_back(*__first);
#endif
if (__notempty)
{
if (begin() == end())
__builtin_unreachable();
}
}
// Called by list(n,v,a), and the range constructor when it turns out
// to be the same thing.
void
_M_fill_initialize(size_type __n, const value_type& __x)
{
for (; __n; --__n)
push_back(__x);
}
#if __cplusplus >= 201103L
// Called by list(n).
void
_M_default_initialize(size_type __n)
{
for (; __n; --__n)
emplace_back();
}
// Called by resize(sz).
void
_M_default_append(size_type __n);
#endif
// Internal assign functions follow.
// Called by the range assign to implement [23.1.1]/9
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 438. Ambiguity in the "do the right thing" clause
template
void
_M_assign_dispatch(_Integer __n, _Integer __val, __true_type)
{ _M_fill_assign(__n, __val); }
// Called by the range assign to implement [23.1.1]/9
template
void
_M_assign_dispatch(_InputIterator __first, _InputIterator __last,
__false_type);
// Called by assign(n,t), and the range assign when it turns out
// to be the same thing.
void
_M_fill_assign(size_type __n, const value_type& __val);
// Moves the elements from [first,last) before position.
void
_M_transfer(iterator __position, iterator __first, iterator __last)
{ __position._M_node->_M_transfer(__first._M_node, __last._M_node); }
// Inserts new element at position given and with value given.
#if __cplusplus < 201103L
void
_M_insert(iterator __position, const value_type& __x)
{
_Node_ptr __tmp = _M_create_node(__x);
__tmp->_M_hook(__position._M_node);
this->_M_inc_size(1);
}
#else
template
void
_M_insert(iterator __position, _Args&&... __args)
{
_Node_ptr __tmp = _M_create_node(std::forward<_Args>(__args)...);
__tmp->_M_hook(__position._M_node);
this->_M_inc_size(1);
}
#endif
// Erases element at position given.
void
_M_erase(iterator __position) _GLIBCXX_NOEXCEPT
{
typedef typename _Node_traits::_Node _Node;
this->_M_dec_size(1);
__position._M_node->_M_unhook();
_Node& __n = static_cast<_Node&>(*__position._M_node);
this->_M_destroy_node(__n._M_node_ptr());
}
// To implement the splice (and merge) bits of N1599.
void
_M_check_equal_allocators(const list& __x) _GLIBCXX_NOEXCEPT
{
if (_M_get_Node_allocator() != __x._M_get_Node_allocator())
__builtin_abort();
}
// Used to implement resize.
const_iterator
_M_resize_pos(size_type& __new_size) const;
#if __cplusplus >= 201103L && ! _GLIBCXX_INLINE_VERSION
// XXX GLIBCXX_ABI Deprecated
// These are unused and only kept so that explicit instantiations will
// continue to define the symbols.
void
_M_move_assign(list&& __x, true_type) noexcept
{
this->clear();
this->_M_move_nodes(std::move(__x));
std::__alloc_on_move(this->_M_get_Node_allocator(),
__x._M_get_Node_allocator());
}
void
_M_move_assign(list&& __x, false_type)
{
if (__x._M_get_Node_allocator() == this->_M_get_Node_allocator())
_M_move_assign(std::move(__x), true_type{});
else
// The rvalue's allocator cannot be moved, or is not equal,
// so we need to individually move each element.
_M_assign_dispatch(std::make_move_iterator(__x.begin()),
std::make_move_iterator(__x.end()),
__false_type{});
}
#endif
#if _GLIBCXX_USE_CXX11_ABI
// Update _M_size members after merging (some of) __src into __dest.
struct _Finalize_merge
{
explicit
_Finalize_merge(list& __dest, list& __src, const iterator& __src_next)
: _M_dest(__dest), _M_src(__src), _M_next(__src_next)
{ }
~_Finalize_merge()
{
// For the common case, _M_next == _M_sec.end() and the std::distance
// call is fast. But if any *iter1 < *iter2 comparison throws then we
// have to count how many elements remain in _M_src.
const size_t __num_unmerged = std::distance(_M_next, _M_src.end());
const size_t __orig_size = _M_src._M_get_size();
_M_dest._M_inc_size(__orig_size - __num_unmerged);
_M_src._M_set_size(__num_unmerged);
}
list& _M_dest;
list& _M_src;
const iterator& _M_next;
#if __cplusplus >= 201103L
_Finalize_merge(const _Finalize_merge&) = delete;
#endif
};
#else
struct _Finalize_merge
{ explicit _Finalize_merge(list&, list&, const iterator&) { } };
#endif
#if !_GLIBCXX_INLINE_VERSION
// XXX GLIBCXX_ABI Deprecated
// These members are unused by std::list now, but we keep them here
// so that an explicit instantiation of std::list will define them.
// This ensures that any objects or libraries compiled against old
// versions of GCC will still be able to use the symbols.
#if _GLIBCXX_USE_CXX11_ABI
static size_t
_S_distance(const_iterator __first, const_iterator __last)
{ return std::distance(__first, __last); }
size_t
_M_node_count() const
{ return this->_M_get_size(); }
#else
static size_t
_S_distance(const_iterator, const_iterator)
{ return 0; }
size_t
_M_node_count() const
{ return std::distance(begin(), end()); }
#endif
#endif // ! INLINE_VERSION
};
#if __cpp_deduction_guides >= 201606
template::value_type,
typename _Allocator = allocator<_ValT>,
typename = _RequireInputIter<_InputIterator>,
typename = _RequireAllocator<_Allocator>>
list(_InputIterator, _InputIterator, _Allocator = _Allocator())
-> list<_ValT, _Allocator>;
#if __glibcxx_containers_ranges // C++ >= 23
template>>
list(from_range_t, _Rg&&, _Allocator = _Allocator())
-> list, _Allocator>;
#endif
#endif
_GLIBCXX_END_NAMESPACE_CXX11
/**
* @brief List equality comparison.
* @param __x A %list.
* @param __y A %list of the same type as @a __x.
* @return True iff the size and elements of the lists are equal.
*
* This is an equivalence relation. It is linear in the size of
* the lists. Lists are considered equivalent if their sizes are
* equal, and if corresponding elements compare equal.
*/
template
_GLIBCXX_NODISCARD
inline bool
operator==(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
{
#if _GLIBCXX_USE_CXX11_ABI
if (__x.size() != __y.size())
return false;
#endif
typedef typename list<_Tp, _Alloc>::const_iterator const_iterator;
const_iterator __end1 = __x.end();
const_iterator __end2 = __y.end();
const_iterator __i1 = __x.begin();
const_iterator __i2 = __y.begin();
while (__i1 != __end1 && __i2 != __end2 && *__i1 == *__i2)
{
++__i1;
++__i2;
}
return __i1 == __end1 && __i2 == __end2;
}
#if __cpp_lib_three_way_comparison
/**
* @brief List ordering relation.
* @param __x A `list`.
* @param __y A `list` of the same type as `__x`.
* @return A value indicating whether `__x` is less than, equal to,
* greater than, or incomparable with `__y`.
*
* See `std::lexicographical_compare_three_way()` for how the determination
* is made. This operator is used to synthesize relational operators like
* `<` and `>=` etc.
*/
template
[[nodiscard]]
inline __detail::__synth3way_t<_Tp>
operator<=>(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
{
return std::lexicographical_compare_three_way(__x.begin(), __x.end(),
__y.begin(), __y.end(),
__detail::__synth3way);
}
#else
/**
* @brief List ordering relation.
* @param __x A %list.
* @param __y A %list of the same type as @a __x.
* @return True iff @a __x is lexicographically less than @a __y.
*
* This is a total ordering relation. It is linear in the size of the
* lists. The elements must be comparable with @c <.
*
* See std::lexicographical_compare() for how the determination is made.
*/
template
_GLIBCXX_NODISCARD
inline bool
operator<(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
{ return std::lexicographical_compare(__x.begin(), __x.end(),
__y.begin(), __y.end()); }
/// Based on operator==
template
_GLIBCXX_NODISCARD
inline bool
operator!=(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
{ return !(__x == __y); }
/// Based on operator<
template
_GLIBCXX_NODISCARD
inline bool
operator>(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
{ return __y < __x; }
/// Based on operator<
template
_GLIBCXX_NODISCARD
inline bool
operator<=(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
{ return !(__y < __x); }
/// Based on operator<
template
_GLIBCXX_NODISCARD
inline bool
operator>=(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
{ return !(__x < __y); }
#endif // three-way comparison
/// See std::list::swap().
template
inline void
swap(list<_Tp, _Alloc>& __x, list<_Tp, _Alloc>& __y)
_GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
{ __x.swap(__y); }
_GLIBCXX_END_NAMESPACE_CONTAINER
#if _GLIBCXX_USE_CXX11_ABI
// Detect when distance is used to compute the size of the whole list.
template
inline ptrdiff_t
__distance(_GLIBCXX_STD_C::_List_iterator<_Tp> __first,
_GLIBCXX_STD_C::_List_iterator<_Tp> __last,
input_iterator_tag __tag)
{
typedef _GLIBCXX_STD_C::_List_const_iterator<_Tp> _CIter;
return std::__distance(_CIter(__first), _CIter(__last), __tag);
}
template
inline ptrdiff_t
__distance(_GLIBCXX_STD_C::_List_const_iterator<_Tp> __first,
_GLIBCXX_STD_C::_List_const_iterator<_Tp> __last,
input_iterator_tag)
{
typedef __detail::_List_node_header _Sentinel;
_GLIBCXX_STD_C::_List_const_iterator<_Tp> __beyond = __last;
++__beyond;
const bool __whole = __first == __beyond;
if (__builtin_constant_p (__whole) && __whole)
return static_cast(__last._M_node)->_M_size;
ptrdiff_t __n = 0;
while (__first != __last)
{
++__first;
++__n;
}
return __n;
}
#if _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
template
inline ptrdiff_t
__distance(__list::_Iterator<_Const, _Ptr> __first,
__list::_Iterator<_Const, _Ptr> __last,
input_iterator_tag __tag)
{
using _Tp = typename __list::_Iterator<_Const, _Ptr>::value_type;
using _Sentinel = typename __list::_Node_traits<_Tp, _Ptr>::_Node_header;
auto __beyond = __last;
++__beyond;
const bool __whole = __first == __beyond;
if (__builtin_constant_p (__whole) && __whole)
return static_cast(*__last._M_node)._M_size;
ptrdiff_t __n = 0;
while (__first != __last)
{
++__first;
++__n;
}
return __n;
}
#endif
#endif
#if _GLIBCXX_USE_ALLOC_PTR_FOR_LIST
namespace __list
{
template
void
_Node_base<_VoidPtr>::swap(_Node_base& __x, _Node_base& __y) noexcept
{
auto __px = __x._M_base();
auto __py = __x._M_base();
if (__x._M_next != __px)
{
if (__y._M_next != __py)
{
using std::swap;
// Both __x and __y are not empty.
swap(__x._M_next,__y._M_next);
swap(__x._M_prev,__y._M_prev);
__x._M_next->_M_prev = __x._M_prev->_M_next = __px;
__y._M_next->_M_prev = __y._M_prev->_M_next = __py;
}
else
{
// __x is not empty, __y is empty.
__y._M_next = __x._M_next;
__y._M_prev = __x._M_prev;
__y._M_next->_M_prev = __y._M_prev->_M_next = __py;
__x._M_next = __x._M_prev = __px;
}
}
else if (__y._M_next != __py)
{
// __x is empty, __y is not empty.
__x._M_next = __y._M_next;
__x._M_prev = __y._M_prev;
__x._M_next->_M_prev = __x._M_prev->_M_next = __px;
__y._M_next = __y._M_prev = __py;
}
}
template
void
_Node_base<_VoidPtr>::_M_transfer(_Base_ptr const __first,
_Base_ptr const __last) noexcept
{
__glibcxx_assert(__first != __last);
auto __self = _M_base();
if (__self != __last)
{
// Remove [first, last) from its old position.
__last->_M_prev->_M_next = __self;
__first->_M_prev->_M_next = __last;
this->_M_prev->_M_next = __first;
// Splice [first, last) into its new position.
auto const __tmp = this->_M_prev;
this->_M_prev = __last->_M_prev;
__last->_M_prev = __first->_M_prev;
__first->_M_prev = __tmp;
}
}
template
void
_Node_header<_VoidPtr>::_M_reverse() noexcept
{
const auto __self = this->_M_base();
auto __tmp = __self;
do
{
using std::swap;
swap(__tmp->_M_next, __tmp->_M_prev);
// Old next node is now prev.
__tmp = __tmp->_M_prev;
}
while (__tmp != __self);
}
} // namespace __list
#endif
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif /* _STL_LIST_H */