import { asyncScheduler } from '../scheduler/async';
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import { defaultThrottleConfig, throttle } from './throttle';
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import { MonoTypeOperatorFunction, SchedulerLike } from '../types';
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import { timer } from '../observable/timer';
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/**
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* Emits a value from the source Observable, then ignores subsequent source
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* values for `duration` milliseconds, then repeats this process.
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*
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* <span class="informal">Lets a value pass, then ignores source values for the
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* next `duration` milliseconds.</span>
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*
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* 
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*
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* `throttleTime` emits the source Observable values on the output Observable
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* when its internal timer is disabled, and ignores source values when the timer
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* is enabled. Initially, the timer is disabled. As soon as the first source
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* value arrives, it is forwarded to the output Observable, and then the timer
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* is enabled. After `duration` milliseconds (or the time unit determined
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* internally by the optional `scheduler`) has passed, the timer is disabled,
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* and this process repeats for the next source value. Optionally takes a
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* {@link SchedulerLike} for managing timers.
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*
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* ## Examples
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*
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* ### Limit click rate
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*
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* Emit clicks at a rate of at most one click per second
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*
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* ```ts
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* import { fromEvent, throttleTime } from 'rxjs';
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*
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* const clicks = fromEvent(document, 'click');
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* const result = clicks.pipe(throttleTime(1000));
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*
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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 sampleTime}
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* @see {@link throttle}
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*
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* @param duration Time to wait before emitting another value after
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* emitting the last value, measured in milliseconds or the time unit determined
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* internally by the optional `scheduler`.
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* @param scheduler The {@link SchedulerLike} to use for
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* managing the timers that handle the throttling. Defaults to {@link asyncScheduler}.
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* @param config a configuration object to define `leading` and
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* `trailing` behavior. Defaults to `{ leading: true, trailing: false }`.
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* @return A function that returns an Observable that performs the throttle
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* operation to limit the rate of emissions from the source.
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*/
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export function throttleTime<T>(
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duration: number,
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scheduler: SchedulerLike = asyncScheduler,
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config = defaultThrottleConfig
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): MonoTypeOperatorFunction<T> {
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const duration$ = timer(duration, scheduler);
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return throttle(() => duration$, config);
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}
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