47 lines
1.9 KiB
JavaScript
47 lines
1.9 KiB
JavaScript
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/** PURE_IMPORTS_START .._scheduler_async,.._operators_sampleTime PURE_IMPORTS_END */
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import { async } from '../scheduler/async';
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import { sampleTime as higherOrder } from '../operators/sampleTime';
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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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* <img src="./img/sampleTime.png" width="100%">
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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 <caption>Every second, emit the most recent click at most once</caption>
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* var clicks = Rx.Observable.fromEvent(document, 'click');
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* var result = clicks.sampleTime(1000);
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* result.subscribe(x => console.log(x));
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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 {Scheduler} [scheduler=async] The {@link IScheduler} 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 function sampleTime(period, scheduler) {
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if (scheduler === void 0) {
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scheduler = async;
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}
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return higherOrder(period, scheduler)(this);
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}
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//# sourceMappingURL=sampleTime.js.map
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