property persist

Source

void set persist(bool val) {
  if (val == _persist) return;
  _persist = val;
  ISubscriptionResponderStorage storageM = response.responder.storage;
  if (storageM != null) {
    if (_persist) {
      _storage = storageM.getOrCreateValue(node.path);
    } else if (_storage != null) {
      storageM.destroyValue(node.path);
      _storage = null;
    }
  }
}