CombinedMapView<K, V> class

Returns a new map that represents maps flattened into a single map.

All methods and accessors treat the new map as-if it were a single concatenated map, but the underlying implementation is based on lazily accessing individual map instances. In the occasion where a key occurs in multiple maps the first value is returned.

The resulting map has an index operator ([]) that is O(maps), rather than O(1), and the map is unmodifiable, but underlying changes to these maps are still accessible from the resulting map.

The length getter is O(M) where M is the total number of entries in all maps, since it has to remove duplicate entries.

Inheritance

Constructors

CombinedMapView(Iterable<Map<K, V>> _maps)
Create a new combined view of multiple maps.

Properties

entries Iterable<MapEntry<K, V>>
The map entries of this.
no setterinherited
hashCode int
The hash code for this object.
no setterinherited
isEmpty bool
Whether there is no key/value pair in the map.
no setterinherited
isNotEmpty bool
Whether there is at least one key/value pair in the map.
no setterinherited
keys Iterable<K>
The keys of this.
no setteroverride
length int
The number of key/value pairs in the map.
no setterinherited
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
values Iterable<V>
The values of this.
no setterinherited

Methods

addAll(Map<K, V> other) → void
This operation is not supported by an unmodifiable map.
inherited
addEntries(Iterable<MapEntry<K, V>> entries) → void
This operation is not supported by an unmodifiable map.
inherited
cast<RK, RV>() Map<RK, RV>
Provides a view of this map as having RK keys and RV instances, if necessary.
inherited
clear() → void
This operation is not supported by an unmodifiable map.
inherited
containsKey(Object? key) bool
Whether this map contains the given key.
inherited
containsValue(Object? value) bool
Whether this map contains the given value.
inherited
forEach(void action(K key, V value)) → void
Applies action to each key/value pair of the map.
inherited
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 convert function.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
putIfAbsent(K key, V ifAbsent()) → V
This operation is not supported by an unmodifiable map.
inherited
remove(Object? key) → V?
This operation is not supported by an unmodifiable map.
inherited
removeWhere(bool test(K key, V value)) → void
This operation is not supported by an unmodifiable map.
inherited
toString() String
A string representation of this object.
inherited
update(K key, V update(V value), {V ifAbsent()?}) → V
This operation is not supported by an unmodifiable map.
inherited
updateAll(V update(K key, V value)) → void
This operation is not supported by an unmodifiable map.
inherited

Operators

operator ==(Object other) bool
The equality operator.
inherited
operator [](Object? key) → V?
The value for the given key, or null if key is not in the map.
override
operator []=(K key, V value) → void
This operation is not supported by an unmodifiable map.
inherited