1 | import { Observable } from '../Observable';
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2 | import { MonoTypeOperatorFunction } from '../types';
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3 | /**
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4 | * Emits the most recently emitted value from the source Observable whenever
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5 | * another Observable, the `notifier`, emits.
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6 | *
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7 | * <span class="informal">It's like {@link sampleTime}, but samples whenever
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8 | * the `notifier` Observable emits something.</span>
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9 | *
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10 | * ![](sample.png)
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11 | *
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12 | * Whenever the `notifier` Observable emits a value or completes, `sample`
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13 | * looks at the source Observable and emits whichever value it has most recently
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14 | * emitted since the previous sampling, unless the source has not emitted
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15 | * anything since the previous sampling. The `notifier` is subscribed to as soon
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16 | * as the output Observable is subscribed.
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17 | *
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18 | * ## Example
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19 | * On every click, sample the most recent "seconds" timer
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20 | * ```ts
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21 | * import { fromEvent, interval } from 'rxjs';
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22 | * import { sample } from 'rxjs/operators';
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23 | *
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24 | * const seconds = interval(1000);
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25 | * const clicks = fromEvent(document, 'click');
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26 | * const result = seconds.pipe(sample(clicks));
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27 | * result.subscribe(x => console.log(x));
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28 | * ```
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29 | *
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30 | * @see {@link audit}
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31 | * @see {@link debounce}
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32 | * @see {@link sampleTime}
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33 | * @see {@link throttle}
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34 | *
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35 | * @param {Observable<any>} notifier The Observable to use for sampling the
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36 | * source Observable.
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37 | * @return {Observable<T>} An Observable that emits the results of sampling the
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38 | * values emitted by the source Observable whenever the notifier Observable
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39 | * emits value or completes.
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40 | * @method sample
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41 | * @owner Observable
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42 | */
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43 | export declare function sample<T>(notifier: Observable<any>): MonoTypeOperatorFunction<T>;
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