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- import { Subscriber } from '../Subscriber';
- import { async } from '../scheduler/async';
- import { defaultThrottleConfig } from './throttle';
- /**
- * Emits a value from the source Observable, then ignores subsequent source
- * values for `duration` milliseconds, then repeats this process.
- *
- * <span class="informal">Lets a value pass, then ignores source values for the
- * next `duration` milliseconds.</span>
- *
- * <img src="./img/throttleTime.png" width="100%">
- *
- * `throttleTime` 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. After `duration` milliseconds (or the time unit determined
- * internally by the optional `scheduler`) has passed, the timer is disabled,
- * and this process repeats for the next source value. Optionally takes a
- * {@link IScheduler} for managing timers.
- *
- * @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.throttleTime(1000);
- * result.subscribe(x => console.log(x));
- *
- * @see {@link auditTime}
- * @see {@link debounceTime}
- * @see {@link delay}
- * @see {@link sampleTime}
- * @see {@link throttle}
- *
- * @param {number} duration Time to wait before emitting another value after
- * emitting the last value, measured in milliseconds or the time unit determined
- * internally by the optional `scheduler`.
- * @param {Scheduler} [scheduler=async] The {@link IScheduler} to use for
- * managing the timers that handle the throttling.
- * @return {Observable<T>} An Observable that performs the throttle operation to
- * limit the rate of emissions from the source.
- * @method throttleTime
- * @owner Observable
- */
- export function throttleTime(duration, scheduler = async, config = defaultThrottleConfig) {
- return (source) => source.lift(new ThrottleTimeOperator(duration, scheduler, config.leading, config.trailing));
- }
- class ThrottleTimeOperator {
- constructor(duration, scheduler, leading, trailing) {
- this.duration = duration;
- this.scheduler = scheduler;
- this.leading = leading;
- this.trailing = trailing;
- }
- call(subscriber, source) {
- return source.subscribe(new ThrottleTimeSubscriber(subscriber, this.duration, this.scheduler, this.leading, this.trailing));
- }
- }
- /**
- * We need this JSDoc comment for affecting ESDoc.
- * @ignore
- * @extends {Ignored}
- */
- class ThrottleTimeSubscriber extends Subscriber {
- constructor(destination, duration, scheduler, leading, trailing) {
- super(destination);
- this.duration = duration;
- this.scheduler = scheduler;
- this.leading = leading;
- this.trailing = trailing;
- this._hasTrailingValue = false;
- this._trailingValue = null;
- }
- _next(value) {
- if (this.throttled) {
- if (this.trailing) {
- this._trailingValue = value;
- this._hasTrailingValue = true;
- }
- }
- else {
- this.add(this.throttled = this.scheduler.schedule(dispatchNext, this.duration, { subscriber: this }));
- if (this.leading) {
- this.destination.next(value);
- }
- }
- }
- clearThrottle() {
- const throttled = this.throttled;
- if (throttled) {
- if (this.trailing && this._hasTrailingValue) {
- this.destination.next(this._trailingValue);
- this._trailingValue = null;
- this._hasTrailingValue = false;
- }
- throttled.unsubscribe();
- this.remove(throttled);
- this.throttled = null;
- }
- }
- }
- function dispatchNext(arg) {
- const { subscriber } = arg;
- subscriber.clearThrottle();
- }
- //# sourceMappingURL=throttleTime.js.map
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