49 lines
1.5 KiB
TypeScript
49 lines
1.5 KiB
TypeScript
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import { MonoTypeOperatorFunction } from '../types';
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/**
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* Emits only the first `count` values emitted by the source Observable.
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*
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* <span class="informal">Takes the first `count` values from the source, then
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* completes.</span>
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*
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* 
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*
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* `take` returns an Observable that emits only the first `count` values emitted
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* by the source Observable. If the source emits fewer than `count` values then
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* all of its values are emitted. After that, it completes, regardless if the
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* source completes.
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*
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* ## Example
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* Take the first 5 seconds of an infinite 1-second interval Observable
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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 intervalCount = interval(1000);
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* const takeFive = intervalCount.pipe(take(5));
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* takeFive.subscribe(x => console.log(x));
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*
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* // Logs:
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* // 0
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* // 1
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* // 2
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* // 3
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* // 4
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* ```
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*
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* @see {@link takeLast}
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* @see {@link takeUntil}
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* @see {@link takeWhile}
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* @see {@link skip}
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*
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* @throws {ArgumentOutOfRangeError} When using `take(i)`, it delivers an
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* ArgumentOutOrRangeError to the Observer's `error` callback if `i < 0`.
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*
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* @param {number} count The maximum number of `next` values to emit.
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* @return {Observable<T>} An Observable that emits only the first `count`
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* values emitted by the source Observable, or all of the values from the source
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* if the source emits fewer than `count` values.
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* @method take
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* @owner Observable
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*/
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export declare function take<T>(count: number): MonoTypeOperatorFunction<T>;
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