flatMapFirst() operator?

[Habib Okanla]

Hi,

I found myself needing an operator which would do what FlatMapFirst (https://github.com/Reactive-Extensions/RxJS/blob/master/doc/api/core/operators/flatmapfirst.md) does, but couldn't find anything for RxJava. Is there a good way to reproduce the same behavior?

Thanks and best,

Habib

[Dávid Karnok]

Hi. If I understand that document properly (no marble there you see), then you can achieve a similar effect by onBackpressurLatest before flatMap(maxConcurrency = 1):

    Observable.interval(0, 1, TimeUnit.SECONDS)

    .onBackpressureLatest()

    .flatMap(v -> Observable.timer(1900, TimeUnit.MILLISECONDS), 1)

    .take(10)

    .toBlocking()

    .subscribe();

--

Best regards,

David Karnok

[Habib Okanla]

Outstanding, thanks Dávid! Today learned that flatmap has a concurrency limit parameter!