import { Observable } from '../Observable';
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import { noop } from '../util/noop';
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/**
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* An Observable that emits no items to the Observer and never completes.
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*
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* 
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*
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* A simple Observable that emits neither values nor errors nor the completion
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* notification. It can be used for testing purposes or for composing with other
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* Observables. Please note that by never emitting a complete notification, this
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* Observable keeps the subscription from being disposed automatically.
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* Subscriptions need to be manually disposed.
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*
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* ## Example
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*
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* Emit the number 7, then never emit anything else (not even complete)
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*
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* ```ts
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* import { NEVER, startWith } from 'rxjs';
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*
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* const info = () => console.log('Will not be called');
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*
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* const result = NEVER.pipe(startWith(7));
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* result.subscribe({
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* next: x => console.log(x),
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* error: info,
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* complete: info
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* });
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* ```
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*
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* @see {@link Observable}
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* @see {@link EMPTY}
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* @see {@link of}
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* @see {@link throwError}
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*/
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export const NEVER = new Observable<never>(noop);
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/**
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* @deprecated Replaced with the {@link NEVER} constant. Will be removed in v8.
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*/
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export function never() {
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return NEVER;
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}
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