throw error inside rxjs Observable

Question

I'm trying to throw an error inside a rxjs Observable

 new Observable(subscriber => {    Observable.throw("error1");    return Observable.throw("error2");  })  .subscribe(    () => {},    err => console.error(err)  ); 

error 1 is not caught.

error2 gives a compilation error:

Argument of type '(this: Observable<{}>, subscriber: Subscriber<{}>) => ErrorObservable<string>' is not assignable to parameter of type '(this: Observable<{}>, subscriber: Subscriber<{}>) => TeardownLogic'. Type 'ErrorObservable<string>' is not assignable to type 'TeardownLogic' 

what is the proper way to throw an error inside an observable?

Answer 1

Use Subscriber.error:

new Rx.Observable(subscriber => {    subscriber.error("error1");    subscriber.error("error2"); // not called because a stream will be finalized after any error  })  .subscribe(    () => {},    err => console.error(err)  );

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