TransactionFn<T extends DataModel<T>> typedef

TransactionFn<T extends DataModel<T>> = FutureOr<T?> Function(String id, T? data)

The transaction function definition.

All transaction get either the data or null and must return data or null. If data is returned, it's DataModel.id must be the same as the transaction id. If this method throws, the transaction is aborted.

Implementation

typedef TransactionFn<T extends DataModel<T>> = FutureOr<T?> Function(
  String id,
  T? data,
);