startWith method
Prepends a given value to the source ReactiveSubject.
Usage:
final subject = ReactiveSubject<int>(initialValue: 1);
final started = subject.startWith(0);
started.stream.listen(print); // Prints: 0, 1
subject.add(2); // Prints: 2
Implementation
ReactiveSubject<T> startWith(T startValue) {
final result = ReactiveSubject<T>(initialValue: startValue);
stream.startWith(startValue).listen(result.add, onError: result.addError);
return result;
}