withDefault method

MapWithDefault<K, V> withDefault(
  1. V value
)

Returns a mutable view of this Map that responds with the provided default value, when the caller tries to access a non-existent key.

As a consequence, the return type of the accessor V operator [](Object? key) is V and not V? like with a standard Map.

For example:

final map = {'a': 1}.withDefault(42);
print(map['z']);  // 42
print(map.containsKey('z'));  // false

Implementation

MapWithDefault<K, V> withDefault(V value) => MapWithDefault(this, value);