1// Copyright (c) 2011 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef BASE_CONTAINERS_HASH_TABLES_H_ 6#define BASE_CONTAINERS_HASH_TABLES_H_ 7 8#include <cstddef> 9#include <unordered_map> 10#include <unordered_set> 11#include <utility> 12 13#include "base/hash.h" 14 15// This header file is deprecated. Use the corresponding C++11 type 16// instead. https://crbug.com/576864 17 18// Use a custom hasher instead. 19#define BASE_HASH_NAMESPACE base_hash 20 21namespace BASE_HASH_NAMESPACE { 22 23// A separate hasher which, by default, forwards to std::hash. This is so legacy 24// uses of BASE_HASH_NAMESPACE with base::hash_map do not interfere with 25// std::hash mid-transition. 26template<typename T> 27struct hash { 28 std::size_t operator()(const T& value) const { return std::hash<T>()(value); } 29}; 30 31// Use base::IntPairHash from base/hash.h as a custom hasher instead. 32template <typename Type1, typename Type2> 33struct hash<std::pair<Type1, Type2>> { 34 std::size_t operator()(std::pair<Type1, Type2> value) const { 35 return base::HashInts(value.first, value.second); 36 } 37}; 38 39} // namespace BASE_HASH_NAMESPACE 40 41namespace base { 42 43// Use std::unordered_map instead. 44template <class Key, 45 class T, 46 class Hash = BASE_HASH_NAMESPACE::hash<Key>, 47 class Pred = std::equal_to<Key>, 48 class Alloc = std::allocator<std::pair<const Key, T>>> 49using hash_map = std::unordered_map<Key, T, Hash, Pred, Alloc>; 50 51// Use std::unordered_multimap instead. 52template <class Key, 53 class T, 54 class Hash = BASE_HASH_NAMESPACE::hash<Key>, 55 class Pred = std::equal_to<Key>, 56 class Alloc = std::allocator<std::pair<const Key, T>>> 57using hash_multimap = std::unordered_multimap<Key, T, Hash, Pred, Alloc>; 58 59// Use std::unordered_multiset instead. 60template <class Key, 61 class Hash = BASE_HASH_NAMESPACE::hash<Key>, 62 class Pred = std::equal_to<Key>, 63 class Alloc = std::allocator<Key>> 64using hash_multiset = std::unordered_multiset<Key, Hash, Pred, Alloc>; 65 66// Use std::unordered_set instead. 67template <class Key, 68 class Hash = BASE_HASH_NAMESPACE::hash<Key>, 69 class Pred = std::equal_to<Key>, 70 class Alloc = std::allocator<Key>> 71using hash_set = std::unordered_set<Key, Hash, Pred, Alloc>; 72 73} // namespace base 74 75#endif // BASE_CONTAINERS_HASH_TABLES_H_ 76