Returns an Observable that mirrors the first source Observable to emit an item.
race<T>(...observables: (Observable<any>[] | Observable<any>)[]): Observable<T>
Parameters
| observables |
Type: (Observable[] | Observable)[].
|
Returns
Observable<T>: an Observable that mirrors the output of the first Observable to emit an item.
Description
Example
Subscribes to the observable that was the first to start emitting.
import { race, interval } from 'rxjs';
import { mapTo } from 'rxjs/operators';
const obs1 = interval(1000).pipe(mapTo('fast one'));
const obs2 = interval(3000).pipe(mapTo('medium one'));
const obs3 = interval(5000).pipe(mapTo('slow one'));
race(obs3, obs1, obs2)
.subscribe(
winner => console.log(winner)
);
// result:
// a series of 'fast one'
Overloads
race(a: Observable<A>, b: Observable<B>): Observable<A> | Observable<B>
Parameters
| a |
Type: Observable.
|
| b |
Type: Observable.
|
Returns
Observable<A> | Observable<B>
|
race(a: Observable<A>, b: Observable<B>, c: Observable<C>): Observable<A> | Observable<B> | Observable<C>
Parameters
| a |
Type: Observable.
|
| b |
Type: Observable.
|
| c |
Type: Observable.
|
Returns
Observable<A> | Observable<B> | Observable<C>
|
race(a: Observable<A>, b: Observable<B>, c: Observable<C>, d: Observable<D>): Observable<A> | Observable<B> | Observable<C> | Observable<D>
Parameters
| a |
Type: Observable.
|
| b |
Type: Observable.
|
| c |
Type: Observable.
|
| d |
Type: Observable.
|
Returns
Observable<A> | Observable<B> | Observable<C> | Observable<D>
|
race(a: Observable<A>, b: Observable<B>, c: Observable<C>, d: Observable<D>, e: Observable<E>): Observable<A> | Observable<B> | Observable<C> | Observable<D> | Observable<E>
Parameters
| a |
Type: Observable.
|
| b |
Type: Observable.
|
| c |
Type: Observable.
|
| d |
Type: Observable.
|
| e |
Type: Observable.
|
Returns
Observable<A> | Observable<B> | Observable<C> | Observable<D> | Observable<E>
|
race(observables: Observable<T>[]): Observable<T>
Parameters
| observables |
Type: Observable[].
|
Returns
Observable<T>
|
race(observables: Observable<any>[]): Observable<{
}>
Parameters
| observables |
Type: Observable[].
|
Returns
Observable<{ }>
|
race(...observables: Observable<T>[]): Observable<T>
Parameters
| observables |
Type: Observable[].
|
Returns
Observable<T>
|
race(...observables: Observable<any>[]): Observable<{
}>
Parameters
| observables |
Type: Observable[].
|
Returns
Observable<{ }>
|