description

# Map<K, V>.unmodifiableOf constructor

1. @Since.new("3.13")

Map<K, V>.unmodifiableOf(

1. Map<K, V> other

)

Creates an unmodifiable hash-based map containing the entries of `other`.

The map requires the keys to implement compatible `operator==` and `hashCode`. The created map iterates keys in a fixed order, preserving the order provided by `other`.

The resulting map behaves like the result of Map.of, except that the map returned by this constructor is not modifiable.

    final planets = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Earth'};
    final unmodifiableMap = Map.unmodifiableOf(planets);
    unmodifiableMap[4] = 'Mars'; // Throws

## Implementation

    @Since("3.13")
    factory Map.unmodifiableOf(Map<K, V> other) = Map<K, V>.unmodifiable;