import { observeNotification } from '../Notification';
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import { OperatorFunction, ObservableNotification, ValueFromNotification } from '../types';
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import { operate } from '../util/lift';
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import { createOperatorSubscriber } from './OperatorSubscriber';
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/**
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* Converts an Observable of {@link ObservableNotification} objects into the emissions
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* that they represent.
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*
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* <span class="informal">Unwraps {@link ObservableNotification} 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 ObservableNotification} 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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*
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* Convert an Observable of Notifications to an actual Observable
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*
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* ```ts
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* import { NextNotification, ErrorNotification, of, dematerialize } from 'rxjs';
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*
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* const notifA: NextNotification<string> = { kind: 'N', value: 'A' };
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* const notifB: NextNotification<string> = { kind: 'N', value: 'B' };
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* const notifE: ErrorNotification = { kind: 'E', error: 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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*
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* const upperCase = materialized.pipe(dematerialize());
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* upperCase.subscribe({
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* next: x => console.log(x),
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* error: e => console.error(e)
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* });
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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 materialize}
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*
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* @return A function that returns an Observable that emits items and
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* notifications embedded in Notification objects emitted by the source
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* Observable.
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*/
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export function dematerialize<N extends ObservableNotification<any>>(): OperatorFunction<N, ValueFromNotification<N>> {
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return operate((source, subscriber) => {
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source.subscribe(createOperatorSubscriber(subscriber, (notification) => observeNotification(notification, subscriber)));
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});
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}
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