publish.ts
1.47 KB
import { Subject } from '../Subject';
import { Observable } from '../Observable';
import { multicast } from './multicast';
import { ConnectableObservable } from '../observable/ConnectableObservable';
/* tslint:disable:max-line-length */
export function publish<T>(this: Observable<T>): ConnectableObservable<T>;
export function publish<T>(this: Observable<T>, selector: selector<T>): Observable<T>;
/* tslint:disable:max-line-length */
/**
* Returns a ConnectableObservable, which is a variety of Observable that waits until its connect method is called
* before it begins emitting items to those Observers that have subscribed to it.
*
* <img src="./img/publish.png" width="100%">
*
* @param {Function} Optional selector function which can use the multicasted source sequence as many times as needed,
* without causing multiple subscriptions to the source sequence.
* Subscribers to the given source will receive all notifications of the source from the time of the subscription on.
* @return a ConnectableObservable that upon connection causes the source Observable to emit items to its Observers.
* @method publish
* @owner Observable
*/
export function publish<T>(this: Observable<T>, selector?: (source: Observable<T>) => Observable<T>): Observable<T> | ConnectableObservable<T> {
return selector ? multicast.call(this, () => new Subject<T>(), selector) :
multicast.call(this, new Subject<T>());
}
export type selector<T> = (source: Observable<T>) => Observable<T>;