Represents the behaviour when there are no listeners. -> Default - does nothing if no listener is registered. -> Error - throws if no one is listening. -> ExactlyOneListener - throws if connect is called more than one time.
Represents the behaviour when there are no listeners.
-> Default - does nothing if no listener is registered.
-> Error - throws if no one is listening.
-> ExactlyOneListener - throws if connect is called more than one time.