45 lines
1.8 KiB
TypeScript
45 lines
1.8 KiB
TypeScript
import { MonoTypeOperatorFunction, SchedulerLike } from '../types';
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/**
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* Emits the most recently emitted value from the source Observable within
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* periodic time intervals.
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*
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* <span class="informal">Samples the source Observable at periodic time
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* intervals, emitting what it samples.</span>
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*
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* 
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*
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* `sampleTime` periodically looks at the source Observable and emits whichever
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* value it has most recently emitted since the previous sampling, unless the
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* source has not emitted anything since the previous sampling. The sampling
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* happens periodically in time every `period` milliseconds (or the time unit
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* defined by the optional `scheduler` argument). The sampling starts as soon as
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* the output Observable is subscribed.
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*
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* ## Example
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* Every second, emit the most recent click at most once
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* ```ts
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* import { fromEvent } from 'rxjs';
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* import { sampleTime } from 'rxjs/operators';
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*
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* const clicks = fromEvent(document, 'click');
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* const result = clicks.pipe(sampleTime(1000));
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* result.subscribe(x => console.log(x));
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* ```
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*
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* @see {@link auditTime}
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* @see {@link debounceTime}
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* @see {@link delay}
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* @see {@link sample}
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* @see {@link throttleTime}
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*
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* @param {number} period The sampling period expressed in milliseconds or the
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* time unit determined internally by the optional `scheduler`.
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* @param {SchedulerLike} [scheduler=async] The {@link SchedulerLike} to use for
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* managing the timers that handle the sampling.
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* @return {Observable<T>} An Observable that emits the results of sampling the
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* values emitted by the source Observable at the specified time interval.
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* @method sampleTime
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* @owner Observable
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*/
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export declare function sampleTime<T>(period: number, scheduler?: SchedulerLike): MonoTypeOperatorFunction<T>;
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