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- import { Observable } from '../Observable';
- /**
- * We need this JSDoc comment for affecting ESDoc.
- * @extends {Ignored}
- * @hide true
- */
- export class EmptyObservable extends Observable {
- constructor(scheduler) {
- super();
- this.scheduler = scheduler;
- }
- /**
- * Creates an Observable that emits no items to the Observer and immediately
- * emits a complete notification.
- *
- * <span class="informal">Just emits 'complete', and nothing else.
- * </span>
- *
- * <img src="./img/empty.png" width="100%">
- *
- * This static operator is useful for creating a simple Observable that only
- * emits the complete notification. It can be used for composing with other
- * Observables, such as in a {@link mergeMap}.
- *
- * @example <caption>Emit the number 7, then complete.</caption>
- * var result = Rx.Observable.empty().startWith(7);
- * result.subscribe(x => console.log(x));
- *
- * @example <caption>Map and flatten only odd numbers to the sequence 'a', 'b', 'c'</caption>
- * var interval = Rx.Observable.interval(1000);
- * var result = interval.mergeMap(x =>
- * x % 2 === 1 ? Rx.Observable.of('a', 'b', 'c') : Rx.Observable.empty()
- * );
- * result.subscribe(x => console.log(x));
- *
- * // Results in the following to the console:
- * // x is equal to the count on the interval eg(0,1,2,3,...)
- * // x will occur every 1000ms
- * // if x % 2 is equal to 1 print abc
- * // if x % 2 is not equal to 1 nothing will be output
- *
- * @see {@link create}
- * @see {@link never}
- * @see {@link of}
- * @see {@link throw}
- *
- * @param {Scheduler} [scheduler] A {@link IScheduler} to use for scheduling
- * the emission of the complete notification.
- * @return {Observable} An "empty" Observable: emits only the complete
- * notification.
- * @static true
- * @name empty
- * @owner Observable
- */
- static create(scheduler) {
- return new EmptyObservable(scheduler);
- }
- static dispatch(arg) {
- const { subscriber } = arg;
- subscriber.complete();
- }
- /** @deprecated internal use only */ _subscribe(subscriber) {
- const scheduler = this.scheduler;
- if (scheduler) {
- return scheduler.schedule(EmptyObservable.dispatch, 0, { subscriber });
- }
- else {
- subscriber.complete();
- }
- }
- }
- //# sourceMappingURL=EmptyObservable.js.map
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