import { Operator } from '../Operator';
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import { Observable } from '../Observable';
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import { Subscriber } from '../Subscriber';
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import { Notification } from '../Notification';
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import { OperatorFunction } from '../types';
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/**
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* Converts an Observable of {@link Notification} objects into the emissions
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* that they represent.
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*
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* <span class="informal">Unwraps {@link Notification} objects as actual `next`,
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* `error` and `complete` emissions. The opposite of {@link materialize}.</span>
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*
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* 
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*
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* `dematerialize` is assumed to operate an Observable that only emits
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* {@link Notification} objects as `next` emissions, and does not emit any
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* `error`. Such Observable is the output of a `materialize` operation. Those
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* notifications are then unwrapped using the metadata they contain, and emitted
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* as `next`, `error`, and `complete` on the output Observable.
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*
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* Use this operator in conjunction with {@link materialize}.
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*
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* ## Example
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* Convert an Observable of Notifications to an actual Observable
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* ```ts
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* import { of, Notification } from 'rxjs';
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* import { dematerialize } from 'rxjs/operators';
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*
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* const notifA = new Notification('N', 'A');
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* const notifB = new Notification('N', 'B');
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* const notifE = new Notification('E', undefined,
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* new TypeError('x.toUpperCase is not a function')
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* );
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* const materialized = of(notifA, notifB, notifE);
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* const upperCase = materialized.pipe(dematerialize());
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* upperCase.subscribe(x => console.log(x), e => console.error(e));
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*
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* // Results in:
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* // A
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* // B
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* // TypeError: x.toUpperCase is not a function
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* ```
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*
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* @see {@link Notification}
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* @see {@link materialize}
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*
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* @return {Observable} An Observable that emits items and notifications
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* embedded in Notification objects emitted by the source Observable.
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* @method dematerialize
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* @owner Observable
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*/
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export function dematerialize<T>(): OperatorFunction<Notification<T>, T> {
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return function dematerializeOperatorFunction(source: Observable<Notification<T>>) {
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return source.lift(new DeMaterializeOperator());
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};
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}
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class DeMaterializeOperator<T extends Notification<any>, R> implements Operator<T, R> {
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call(subscriber: Subscriber<any>, source: any): any {
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return source.subscribe(new DeMaterializeSubscriber(subscriber));
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}
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}
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/**
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* We need this JSDoc comment for affecting ESDoc.
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* @ignore
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* @extends {Ignored}
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*/
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class DeMaterializeSubscriber<T extends Notification<any>> extends Subscriber<T> {
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constructor(destination: Subscriber<any>) {
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super(destination);
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}
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protected _next(value: T) {
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value.observe(this.destination);
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}
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}
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