unordered_map.h File Reference

Optimized unordered map implementations. More...

#include <string>
#include <map>
#include <ska_hash/unordered_map.hpp>
#include <unordered_map>

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Classes
class	qb::string_to_lower
	Utility class for case-insensitive string operations. More...
class	qb::icase_basic_map< _Map, _Trait >
	A case-insensitive map implementation. More...

Typedefs
template<typename K, typename V, typename H = std::hash<K>, typename E = std::equal_to<K>, typename A = std::allocator<std::pair<const K, V>>>
using	qb::unordered_flat_map = ska::flat_hash_map<K, V, H, E, A>
	A high-performance flat hash map implementation.
template<typename K, typename V, typename H = std::hash<K>, typename E = std::equal_to<K>, typename A = std::allocator<std::pair<const K, V>>>
using	qb::unordered_map = std::unordered_map<K, V, H, E, A>
	The primary unordered map implementation.
template<typename Value, typename _Trait = string_to_lower>
using	qb::icase_map = icase_basic_map<std::map<std::string, Value>, _Trait>
	Case-insensitive ordered map using std::map.
template<typename Value, typename _Trait = string_to_lower>
using	qb::icase_unordered_map
	Case-insensitive unordered map using qb::unordered_map.

Detailed Description

Optimized unordered map implementations.

This file provides optimized and specialized unordered map implementations for the QB framework. It includes high-performance alternatives to the standard unordered_map using flat hash maps from the ska_hash library, and case-insensitive string map implementations.

Author

qb - C++ Actor Framework

Copyright

Copyright (c) 2011-2025 qb - isndev (cpp.actor) Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Typedef Documentation

unordered_flat_map

template<typename K, typename V, typename H = std::hash<K>, typename E = std::equal_to<K>, typename A = std::allocator<std::pair<const K, V>>>

using qb::unordered_flat_map = ska::flat_hash_map<K, V, H, E, A>

A high-performance flat hash map implementation.

This is a type alias for ska::flat_hash_map which provides better performance characteristics than std::unordered_map for many use cases. It uses open addressing with robin hood hashing for better cache locality and performance.

Template Parameters

K	The key type
V	The value type
H	The hash function type (defaults to std::hash<K>)
E	The equality function type (defaults to std::equal_to<K>)
A	The allocator type

icase_map

template<typename Value, typename _Trait = string_to_lower>

using qb::icase_map = icase_basic_map<std::map<std::string, Value>, _Trait>

Case-insensitive ordered map using std::map.

Template Parameters

Value	The value type
_Trait	The trait class for string conversion (defaults to string_to_lower)

icase_unordered_map

template<typename Value, typename _Trait = string_to_lower>

using qb::icase_unordered_map

Initial value:

 
    icase_basic_map<qb::unordered_map<std::string, Value>, _Trait>

Case-insensitive unordered map using qb::unordered_map.

Template Parameters

Value	The value type
_Trait	The trait class for string conversion (defaults to string_to_lower)