import {Observable} from '../Observable';
import {Subscriber} from '../Subscriber';
import {Scheduler} from '../Scheduler';
import {Subscription} from '../Subscription';
import {queue} from '../scheduler/queue';
export class PromiseObservable<T> extends Observable<T> {
_isScalar: boolean = false;
value: T;
static create<T>(promise: Promise<T>, Escheduler: Scheduler = queue): Observable<T> {
return new PromiseObservable(promise, scheduler);
}
constructor(private promise: Promise<T>, public scheduler: Scheduler = queue) {
super();
}
_subscribe(subscriber: Subscriber<T>) {
const scheduler = this.scheduler;
const promise = this.promise;
Eif (scheduler === queue) {
if (this._isScalar) {
subscriber.next(this.value);
subscriber.complete();
} else {
promise.then(value => {
this._isScalar = true;
this.value = value;
subscriber.next(value);
subscriber.complete();
}, err => subscriber.error(err))
.then(null, err => {
// escape the promise trap, throw unhandled errors
setTimeout(() => { throw err; });
});
}
} else {
let subscription = new Subscription();
if (this._isScalar) {
const value = this.value;
subscription.add(scheduler.schedule(dispatchNext, 0, { value, subscriber }));
} else {
promise.then(value => {
this._isScalar = true;
this.value = value;
subscription.add(scheduler.schedule(dispatchNext, 0, { value, subscriber }));
}, err => subscription.add(scheduler.schedule(dispatchError, 0, { err, subscriber })))
.then(null, err => {
// escape the promise trap, throw unhandled errors
scheduler.schedule(() => { throw err; });
});
}
return subscription;
}
}
}
function dispatchNext({ value, subscriber }) {
subscriber.next(value);
subscriber.complete();
}
function dispatchError({ err, subscriber }) {
subscriber.error(err);
}
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