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

49 lines
2.2 KiB
TypeScript

import { SubscribableOrPromise } from '../Observable';
import { MonoTypeOperatorFunction } from '../interfaces';
export interface ThrottleConfig {
leading?: boolean;
trailing?: boolean;
}
export declare const defaultThrottleConfig: ThrottleConfig;
/**
* Emits a value from the source Observable, then ignores subsequent source
* values for a duration determined by another Observable, then repeats this
* process.
*
* <span class="informal">It's like {@link throttleTime}, but the silencing
* duration is determined by a second Observable.</span>
*
* <img src="./img/throttle.png" width="100%">
*
* `throttle` emits the source Observable values on the output Observable
* when its internal timer is disabled, and ignores source values when the timer
* is enabled. Initially, the timer is disabled. As soon as the first source
* value arrives, it is forwarded to the output Observable, and then the timer
* is enabled by calling the `durationSelector` function with the source value,
* which returns the "duration" Observable. When the duration Observable emits a
* value or completes, the timer is disabled, and this process repeats for the
* next source value.
*
* @example <caption>Emit clicks at a rate of at most one click per second</caption>
* var clicks = Rx.Observable.fromEvent(document, 'click');
* var result = clicks.throttle(ev => Rx.Observable.interval(1000));
* result.subscribe(x => console.log(x));
*
* @see {@link audit}
* @see {@link debounce}
* @see {@link delayWhen}
* @see {@link sample}
* @see {@link throttleTime}
*
* @param {function(value: T): SubscribableOrPromise} durationSelector A function
* that receives a value from the source Observable, for computing the silencing
* duration for each source value, returned as an Observable or a Promise.
* @param {Object} config a configuration object to define `leading` and `trailing` behavior. Defaults
* to `{ leading: true, trailing: false }`.
* @return {Observable<T>} An Observable that performs the throttle operation to
* limit the rate of emissions from the source.
* @method throttle
* @owner Observable
*/
export declare function throttle<T>(durationSelector: (value: T) => SubscribableOrPromise<number>, config?: ThrottleConfig): MonoTypeOperatorFunction<T>;