[6a3a178] | 1 | import { Observable } from '../Observable';
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| 2 | import { Operator } from '../Operator';
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| 3 | import { Subscriber } from '../Subscriber';
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| 4 | import { OperatorFunction } from '../types';
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| 5 |
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| 6 | /**
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| 7 | * Ignores all items emitted by the source Observable and only passes calls of `complete` or `error`.
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| 8 | *
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| 9 | * ![](ignoreElements.png)
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| 10 | *
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| 11 | * ## Examples
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| 12 | * ### Ignores emitted values, reacts to observable's completion.
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| 13 | * ```ts
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| 14 | * import { of } from 'rxjs';
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| 15 | * import { ignoreElements } from 'rxjs/operators';
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| 16 | *
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| 17 | * of('you', 'talking', 'to', 'me').pipe(
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| 18 | * ignoreElements(),
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| 19 | * )
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| 20 | * .subscribe(
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| 21 | * word => console.log(word),
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| 22 | * err => console.log('error:', err),
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| 23 | * () => console.log('the end'),
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| 24 | * );
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| 25 | * // result:
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| 26 | * // 'the end'
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| 27 | * ```
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| 28 | * @return {Observable} An empty Observable that only calls `complete`
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| 29 | * or `error`, based on which one is called by the source Observable.
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| 30 | * @method ignoreElements
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| 31 | * @owner Observable
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| 32 | */
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| 33 | export function ignoreElements(): OperatorFunction<any, never> {
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| 34 | return function ignoreElementsOperatorFunction(source: Observable<any>) {
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| 35 | return source.lift(new IgnoreElementsOperator());
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| 36 | };
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| 37 | }
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| 38 |
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| 39 | class IgnoreElementsOperator<T, R> implements Operator<T, R> {
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| 40 | call(subscriber: Subscriber<R>, source: any): any {
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| 41 | return source.subscribe(new IgnoreElementsSubscriber(subscriber));
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| 42 | }
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| 43 | }
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| 44 |
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| 45 | /**
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| 46 | * We need this JSDoc comment for affecting ESDoc.
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| 47 | * @ignore
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| 48 | * @extends {Ignored}
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| 49 | */
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| 50 | class IgnoreElementsSubscriber<T> extends Subscriber<T> {
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| 51 | protected _next(unused: T): void {
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| 52 | // Do nothing
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| 53 | }
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| 54 | }
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