43 lines
1.6 KiB
TypeScript
43 lines
1.6 KiB
TypeScript
import { Observable } from '../Observable';
|
|
import { MonoTypeOperatorFunction } from '../types';
|
|
/**
|
|
* Emits the most recently emitted value from the source Observable whenever
|
|
* another Observable, the `notifier`, emits.
|
|
*
|
|
* <span class="informal">It's like {@link sampleTime}, but samples whenever
|
|
* the `notifier` Observable emits something.</span>
|
|
*
|
|
* 
|
|
*
|
|
* Whenever the `notifier` Observable emits a value or completes, `sample`
|
|
* looks at the source Observable and emits whichever value it has most recently
|
|
* emitted since the previous sampling, unless the source has not emitted
|
|
* anything since the previous sampling. The `notifier` is subscribed to as soon
|
|
* as the output Observable is subscribed.
|
|
*
|
|
* ## Example
|
|
* On every click, sample the most recent "seconds" timer
|
|
* ```ts
|
|
* import { fromEvent, interval } from 'rxjs';
|
|
* import { sample } from 'rxjs/operators';
|
|
*
|
|
* const seconds = interval(1000);
|
|
* const clicks = fromEvent(document, 'click');
|
|
* const result = seconds.pipe(sample(clicks));
|
|
* result.subscribe(x => console.log(x));
|
|
* ```
|
|
*
|
|
* @see {@link audit}
|
|
* @see {@link debounce}
|
|
* @see {@link sampleTime}
|
|
* @see {@link throttle}
|
|
*
|
|
* @param {Observable<any>} notifier The Observable to use for sampling the
|
|
* source Observable.
|
|
* @return {Observable<T>} An Observable that emits the results of sampling the
|
|
* values emitted by the source Observable whenever the notifier Observable
|
|
* emits value or completes.
|
|
* @method sample
|
|
* @owner Observable
|
|
*/
|
|
export declare function sample<T>(notifier: Observable<any>): MonoTypeOperatorFunction<T>;
|