RxJS: Treat first case specially, but continue streaming the rest

user_1772334 0
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Say I wanted to separately handle the first event emitted by an Observable, but then continue my subscription.

For example, if I had the following chain:

observable.throttleTime(2000)
      .takeFirst(() => console.log('potato'))
      .switchMap((event:MouseEvent) => {
        const element:Element = event.target as Element;
        return this.innerObservable(('tomato'));
      })
      .subscribe(({result}) => console.log(result))

That fails, but how would I go about making such behaviour work?

observers rxjs reactive-programming javascript
4 Answers

Simple solution to treat the first separately would be

let isFirstCame= false;

 observable
      .subscribe(({result}) =>
         if(!isFirst){
            //here is our first one
            doSpecialWithTheFirst(result);
            isFirstCame=true;
         }else{
           //All the remaining
           doOtherWithRemaining();
         })
user_44418790
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