update method

@override Future<void> update(K key, V update(V V))

Implementation

@override
Future<void> update(key, V Function(V V) update) async {
  _isInitialized();
  final value = update(_getData(key));
  logger.d('Updating value');
  logger.v({
    'type': "method",
    'method': "update",
    'key': key,
    'updatedValue': toJson(value),
  });
  map[key] = value;
  await _persist();
}