map<K2, V2> method
Returns a new map where all entries of this map are transformed by
the given convert
function.
Implementation
@override
Map<K2, V2> map<K2, V2>(Object Function(K key, V value) transform) {
// TODO(cbracken): Dart 2.0 requires this method to be implemented.
// Change Object to MapEntry<K2, V2> when
// the MapEntry class has been added.
throw UnimplementedError('map');
}