operator [] method
Return a StreamSubscription from the list with a specified key
For example:
StreamSubscription subscription = subxMap[0];
Implementation
StreamSubscription? operator [](Object key) => _subscriptionMap[key];
Return a StreamSubscription from the list with a specified key
For example:
StreamSubscription subscription = subxMap[0];
StreamSubscription? operator [](Object key) => _subscriptionMap[key];