1 | import { MonoTypeOperatorFunction, SubscribableOrPromise } from '../types';
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2 | export interface ThrottleConfig {
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3 | leading?: boolean;
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4 | trailing?: boolean;
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5 | }
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6 | export declare const defaultThrottleConfig: ThrottleConfig;
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7 | /**
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8 | * Emits a value from the source Observable, then ignores subsequent source
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9 | * values for a duration determined by another Observable, then repeats this
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10 | * process.
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11 | *
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12 | * <span class="informal">It's like {@link throttleTime}, but the silencing
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13 | * duration is determined by a second Observable.</span>
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14 | *
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15 | * ![](throttle.png)
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16 | *
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17 | * `throttle` emits the source Observable values on the output Observable
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18 | * when its internal timer is disabled, and ignores source values when the timer
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19 | * is enabled. Initially, the timer is disabled. As soon as the first source
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20 | * value arrives, it is forwarded to the output Observable, and then the timer
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21 | * is enabled by calling the `durationSelector` function with the source value,
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22 | * which returns the "duration" Observable. When the duration Observable emits a
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23 | * value or completes, the timer is disabled, and this process repeats for the
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24 | * next source value.
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25 | *
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26 | * ## Example
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27 | * Emit clicks at a rate of at most one click per second
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28 | * ```ts
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29 | * import { fromEvent } from 'rxjs';
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30 | * import { throttle } from 'rxjs/operators';
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31 | *
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32 | * const clicks = fromEvent(document, 'click');
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33 | * const result = clicks.pipe(throttle(ev => interval(1000)));
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34 | * result.subscribe(x => console.log(x));
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35 | * ```
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36 | *
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37 | * @see {@link audit}
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38 | * @see {@link debounce}
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39 | * @see {@link delayWhen}
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40 | * @see {@link sample}
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41 | * @see {@link throttleTime}
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42 | *
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43 | * @param {function(value: T): SubscribableOrPromise} durationSelector A function
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44 | * that receives a value from the source Observable, for computing the silencing
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45 | * duration for each source value, returned as an Observable or a Promise.
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46 | * @param {Object} config a configuration object to define `leading` and `trailing` behavior. Defaults
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47 | * to `{ leading: true, trailing: false }`.
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48 | * @return {Observable<T>} An Observable that performs the throttle operation to
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49 | * limit the rate of emissions from the source.
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50 | * @method throttle
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51 | * @owner Observable
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52 | */
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53 | export declare function throttle<T>(durationSelector: (value: T) => SubscribableOrPromise<any>, config?: ThrottleConfig): MonoTypeOperatorFunction<T>;
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