52 lines
1.7 KiB
TypeScript
52 lines
1.7 KiB
TypeScript
import { Observable } from '../Observable';
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import { SchedulerLike } from '../types';
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/**
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* Creates an Observable that emits sequential numbers every specified
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* interval of time, on a specified {@link SchedulerLike}.
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*
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* <span class="informal">Emits incremental numbers periodically in time.
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* </span>
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*
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* 
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*
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* `interval` returns an Observable that emits an infinite sequence of
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* ascending integers, with a constant interval of time of your choosing
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* between those emissions. The first emission is not sent immediately, but
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* only after the first period has passed. By default, this operator uses the
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* `async` {@link SchedulerLike} to provide a notion of time, but you may pass any
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* {@link SchedulerLike} to it.
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*
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* ## Example
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* Emits ascending numbers, one every second (1000ms) up to the number 3
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* ```ts
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* import { interval } from 'rxjs';
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* import { take } from 'rxjs/operators';
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*
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* const numbers = interval(1000);
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*
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* const takeFourNumbers = numbers.pipe(take(4));
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*
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* takeFourNumbers.subscribe(x => console.log('Next: ', x));
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*
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* // Logs:
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* // Next: 0
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* // Next: 1
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* // Next: 2
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* // Next: 3
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* ```
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*
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* @see {@link timer}
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* @see {@link delay}
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*
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* @param {number} [period=0] The interval size in milliseconds (by default)
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* or the time unit determined by the scheduler's clock.
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* @param {SchedulerLike} [scheduler=async] The {@link SchedulerLike} to use for scheduling
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* the emission of values, and providing a notion of "time".
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* @return {Observable} An Observable that emits a sequential number each time
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* interval.
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* @static true
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* @name interval
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* @owner Observable
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*/
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export declare function interval(period?: number, scheduler?: SchedulerLike): Observable<number>;
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