MapMixin<K, V> class

Mixin implementing a Map.

This mixin has a basic implementation of all but five of the members of Map. A basic Map class can be implemented by mixin in this class and implementing keys, operator[], operator[]=, remove and clear. The remaining operations are implemented in terms of these five.

The keys iterable should have efficient Iterable.length and Iterable.contains operations, and it should catch concurrent modifications of the keys while iterating.

A more efficient implementation is usually possible by overriding some of the other members as well.

Implemented by




entries Iterable<MapEntry<K, V>>
The map entries of this.
isEmpty bool
Returns true if there is no key/value pair in the map.
isNotEmpty bool
Returns true if there is at least one key/value pair in the map.
keys Iterable<K>
The keys of this. [...]
length int
The number of key/value pairs in the map.
values Iterable<V>
The values of this. [...]
hashCode int
The hash code for this object. [...]
read-only, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited


addAll(Map<K, V> other) → void
Adds all key/value pairs of other to this map. [...]
addEntries(Iterable<MapEntry<K, V>> newEntries) → void
Adds all key/value pairs of newEntries to this map. [...]
cast<RK, RV>() Map<RK, RV>
Provides a view of this map as having RK keys and RV instances, if necessary. [...]
clear() → void
Removes all pairs from the map. [...]
containsKey(Object key) bool
Returns true if this map contains the given key. [...]
containsValue(Object value) bool
Returns true if this map contains the given value. [...]
forEach(void action(K key, V value)) → void
Applies f to each key/value pair of the map. [...]
map<K2, V2>(MapEntry<K2, V2> transform(K key, V value)) Map<K2, V2>
Returns a new map where all entries of this map are transformed by the given f function.
putIfAbsent(K key, V ifAbsent()) → V
Look up the value of key, or add a new value if it isn't there. [...]
remove(Object key) → V
Removes key and its associated value, if present, from the map. [...]
removeWhere(bool test(K key, V value)) → void
Removes all entries of this map that satisfy the given predicate.
toString() String
Returns a string representation of this object.
update(K key, V update(V value), { V ifAbsent() }) → V
Updates the value for the provided key. [...]
updateAll(V update(K key, V value)) → void
Updates all values. [...]
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]


operator [](Object key) → V
Returns the value for the given key or null if key is not in the map. [...]
operator []=(K key, V value) → void
Associates the key with the given value. [...]
operator ==(dynamic other) bool
The equality operator. [...]