unordered_map
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// <unordered_map> -*- C++ -*-
// Copyright (C) 2007-2026 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 include/unordered_map
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_UNORDERED_MAP
#define _GLIBCXX_UNORDERED_MAP 1
#ifdef _GLIBCXX_SYSHDR
#pragma GCC system_header
#endif
#include <bits/requires_hosted.h> // container
#if __cplusplus < 201103L
# include <bits/c++0x_warning.h>
#else
#include <initializer_list>
#include <bits/unordered_map.h>
#include <bits/range_access.h>
#include <bits/erase_if.h>
#ifdef _GLIBCXX_DEBUG
# include <debug/unordered_map>
#endif
#define __glibcxx_want_allocator_traits_is_always_equal
#define __glibcxx_want_containers_ranges
#define __glibcxx_want_erase_if
#define __glibcxx_want_generic_unordered_lookup
#define __glibcxx_want_node_extract
#define __glibcxx_want_nonmember_container_access
#define __glibcxx_want_unordered_map_try_emplace
#define __glibcxx_want_tuple_like
#define __glibcxx_want_associative_heterogeneous_erasure
#define __glibcxx_want_associative_heterogeneous_insertion
#include <bits/version.h>
#if __cplusplus >= 201703L
#include <bits/memory_resource.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
namespace pmr
{
template<typename _Key, typename _Tp, typename _Hash = std::hash<_Key>,
typename _Pred = std::equal_to<_Key>>
using unordered_map
= std::unordered_map<_Key, _Tp, _Hash, _Pred,
polymorphic_allocator<pair<const _Key, _Tp>>>;
template<typename _Key, typename _Tp, typename _Hash = std::hash<_Key>,
typename _Pred = std::equal_to<_Key>>
using unordered_multimap
= std::unordered_multimap<_Key, _Tp, _Hash, _Pred,
polymorphic_allocator<pair<const _Key, _Tp>>>;
} // namespace pmr
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // C++17
#ifdef __cpp_lib_erase_if // C++ >= 20 && HOSTED
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _Key, typename _Tp, typename _Hash, typename _CPred,
typename _Alloc, typename _Predicate>
inline typename _GLIBCXX_STD_C::unordered_map<_Key, _Tp, _Hash,
_CPred, _Alloc>::size_type
erase_if(_GLIBCXX_STD_C::unordered_map<_Key, _Tp, _Hash,
_CPred, _Alloc>& __cont,
_Predicate __pred)
{ return __detail::__erase_nodes_if(__cont, __cont, __pred); }
template<typename _Key, typename _Tp, typename _Hash, typename _CPred,
typename _Alloc, typename _Predicate>
inline typename _GLIBCXX_STD_C::unordered_multimap<_Key, _Tp, _Hash,
_CPred, _Alloc>::size_type
erase_if(_GLIBCXX_STD_C::unordered_multimap<_Key, _Tp, _Hash,
_CPred, _Alloc>& __cont,
_Predicate __pred)
{ return __detail::__erase_nodes_if(__cont, __cont, __pred); }
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // __cpp_lib_erase_if
#endif // C++11
#endif // _GLIBCXX_UNORDERED_MAP
initializer_list
range_access.h
unordered_map.h
version.h
c++0x_warning.h
memory_resource.h
erase_if.h
requires_hosted.h
std
ISO C++ entities toplevel namespace is std.
std::pmr::polymorphic_allocator
Class template polymorphic_allocator.
Definition memory_resource.h:124
unordered_map