blob: cc9bc7b745e9277bf99502fa7b788a066a5b61db [file] [log] [blame]
import { MonoTypeOperatorFunction, SchedulerLike } from '../types';
/**
* Emits a value from the source Observable only after a particular time span
* has passed without another source emission.
*
* <span class="informal">It's like {@link delay}, but passes only the most
* recent value from each burst of emissions.</span>
*
* ![](debounceTime.png)
*
* `debounceTime` delays values emitted by the source Observable, but drops
* previous pending delayed emissions if a new value arrives on the source
* Observable. This operator keeps track of the most recent value from the
* source Observable, and emits that only when `dueTime` enough time has passed
* without any other value appearing on the source Observable. If a new value
* appears before `dueTime` silence occurs, the previous value will be dropped
* and will not be emitted on the output Observable.
*
* This is a rate-limiting operator, because it is impossible for more than one
* value to be emitted in any time window of duration `dueTime`, but it is also
* a delay-like operator since output emissions do not occur at the same time as
* they did on the source Observable. Optionally takes a {@link SchedulerLike} for
* managing timers.
*
* ## Example
* Emit the most recent click after a burst of clicks
* ```ts
* import { fromEvent } from 'rxjs';
* import { debounceTime } from 'rxjs/operators';
*
* const clicks = fromEvent(document, 'click');
* const result = clicks.pipe(debounceTime(1000));
* result.subscribe(x => console.log(x));
* ```
*
* @see {@link auditTime}
* @see {@link debounce}
* @see {@link delay}
* @see {@link sampleTime}
* @see {@link throttleTime}
*
* @param {number} dueTime The timeout duration in milliseconds (or the time
* unit determined internally by the optional `scheduler`) for the window of
* time required to wait for emission silence before emitting the most recent
* source value.
* @param {SchedulerLike} [scheduler=async] The {@link SchedulerLike} to use for
* managing the timers that handle the timeout for each value.
* @return {Observable} An Observable that delays the emissions of the source
* Observable by the specified `dueTime`, and may drop some values if they occur
* too frequently.
* @method debounceTime
* @owner Observable
*/
export declare function debounceTime<T>(dueTime: number, scheduler?: SchedulerLike): MonoTypeOperatorFunction<T>;