PersistentHashMap<K extends Object, V> class Null safety

A collection of key/value pairs which provides efficient retrieval of value by key.

This class implements a persistent map: extending this map with a new key/value pair does not modify an existing instance but instead creates a new instance.

Unlike Map, this class does not support null as a key value and implements only a functionality needed for a specific use case at the core of the framework.

Underlying implementation uses a variation of hash array mapped trie data structure with compressed (bitmap indexed) nodes.

See also:

Constructors

PersistentHashMap.empty()
Creates an empty hash map.
const

Properties

hashCode → int
The hash code for this object.
read-onlyinherited
runtimeType → Type
A representation of the runtime type of the object.
read-onlyinherited

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
inherited
put(K key, V value) → PersistentHashMap<K, V>
If this map does not already contain the given key to value mapping then create a new version of the map which contains all mappings from the current one plus the given key to value mapping.
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited
operator [](K key) → V?
Returns value associated with the given key or null if key is not in the map.