work.suroh.tk/node_modules/rxjs/operators/windowWhen.d.ts

42 lines
1.8 KiB
TypeScript

import { Observable } from '../Observable';
import { OperatorFunction } from '../interfaces';
/**
* Branch out the source Observable values as a nested Observable using a
* factory function of closing Observables to determine when to start a new
* window.
*
* <span class="informal">It's like {@link bufferWhen}, but emits a nested
* Observable instead of an array.</span>
*
* <img src="./img/windowWhen.png" width="100%">
*
* Returns an Observable that emits windows of items it collects from the source
* Observable. The output Observable emits connected, non-overlapping windows.
* It emits the current window and opens a new one whenever the Observable
* produced by the specified `closingSelector` function emits an item. The first
* window is opened immediately when subscribing to the output Observable.
*
* @example <caption>Emit only the first two clicks events in every window of [1-5] random seconds</caption>
* var clicks = Rx.Observable.fromEvent(document, 'click');
* var result = clicks
* .windowWhen(() => Rx.Observable.interval(1000 + Math.random() * 4000))
* .map(win => win.take(2)) // each window has at most 2 emissions
* .mergeAll(); // flatten the Observable-of-Observables
* result.subscribe(x => console.log(x));
*
* @see {@link window}
* @see {@link windowCount}
* @see {@link windowTime}
* @see {@link windowToggle}
* @see {@link bufferWhen}
*
* @param {function(): Observable} closingSelector A function that takes no
* arguments and returns an Observable that signals (on either `next` or
* `complete`) when to close the previous window and start a new one.
* @return {Observable<Observable<T>>} An observable of windows, which in turn
* are Observables.
* @method windowWhen
* @owner Observable
*/
export declare function windowWhen<T>(closingSelector: () => Observable<any>): OperatorFunction<T, Observable<T>>;