void ISubjectSync.Unsubscribe(ISubjectObserver observer) { _observers.Remove(observer); }
void ISubjectSync.Unsubscribe(ISubjectObserver observer) { _observers.Remove(observer); }
void ISubjectSync.Subscribe(ISubjectObserver observer) { _observers.Add(observer); }
void ISubjectSync.Subscribe(ISubjectObserver observer) { _observers.Add(observer); }