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- import { Observable, SubscribableOrPromise } from '../Observable';
- import { Subscriber } from '../Subscriber';
- import { Subscription } from '../Subscription';
- /**
- * We need this JSDoc comment for affecting ESDoc.
- * @extends {Ignored}
- * @hide true
- */
- export declare class DeferObservable<T> extends Observable<T> {
- private observableFactory;
- /**
- * Creates an Observable that, on subscribe, calls an Observable factory to
- * make an Observable for each new Observer.
- *
- * <span class="informal">Creates the Observable lazily, that is, only when it
- * is subscribed.
- * </span>
- *
- * <img src="./img/defer.png" width="100%">
- *
- * `defer` allows you to create the Observable only when the Observer
- * subscribes, and create a fresh Observable for each Observer. It waits until
- * an Observer subscribes to it, and then it generates an Observable,
- * typically with an Observable factory function. It does this afresh for each
- * subscriber, so although each subscriber may think it is subscribing to the
- * same Observable, in fact each subscriber gets its own individual
- * Observable.
- *
- * @example <caption>Subscribe to either an Observable of clicks or an Observable of interval, at random</caption>
- * var clicksOrInterval = Rx.Observable.defer(function () {
- * if (Math.random() > 0.5) {
- * return Rx.Observable.fromEvent(document, 'click');
- * } else {
- * return Rx.Observable.interval(1000);
- * }
- * });
- * clicksOrInterval.subscribe(x => console.log(x));
- *
- * // Results in the following behavior:
- * // If the result of Math.random() is greater than 0.5 it will listen
- * // for clicks anywhere on the "document"; when document is clicked it
- * // will log a MouseEvent object to the console. If the result is less
- * // than 0.5 it will emit ascending numbers, one every second(1000ms).
- *
- * @see {@link create}
- *
- * @param {function(): SubscribableOrPromise} observableFactory The Observable
- * factory function to invoke for each Observer that subscribes to the output
- * Observable. May also return a Promise, which will be converted on the fly
- * to an Observable.
- * @return {Observable} An Observable whose Observers' subscriptions trigger
- * an invocation of the given Observable factory function.
- * @static true
- * @name defer
- * @owner Observable
- */
- static create<T>(observableFactory: () => SubscribableOrPromise<T> | void): Observable<T>;
- constructor(observableFactory: () => SubscribableOrPromise<T> | void);
- /** @deprecated internal use only */ _subscribe(subscriber: Subscriber<T>): Subscription;
- }
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