70 lines
2.3 KiB
JavaScript
70 lines
2.3 KiB
JavaScript
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import { OuterSubscriber } from '../OuterSubscriber';
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import { InnerSubscriber } from '../InnerSubscriber';
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import { subscribeToResult } from '../util/subscribeToResult';
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import { map } from './map';
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import { from } from '../observable/from';
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export function switchMap(project, resultSelector) {
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if (typeof resultSelector === 'function') {
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return (source) => source.pipe(switchMap((a, i) => from(project(a, i)).pipe(map((b, ii) => resultSelector(a, b, i, ii)))));
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}
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return (source) => source.lift(new SwitchMapOperator(project));
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}
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class SwitchMapOperator {
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constructor(project) {
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this.project = project;
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}
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call(subscriber, source) {
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return source.subscribe(new SwitchMapSubscriber(subscriber, this.project));
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}
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}
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class SwitchMapSubscriber extends OuterSubscriber {
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constructor(destination, project) {
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super(destination);
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this.project = project;
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this.index = 0;
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}
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_next(value) {
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let result;
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const index = this.index++;
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try {
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result = this.project(value, index);
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}
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catch (error) {
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this.destination.error(error);
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return;
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}
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this._innerSub(result, value, index);
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}
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_innerSub(result, value, index) {
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const innerSubscription = this.innerSubscription;
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if (innerSubscription) {
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innerSubscription.unsubscribe();
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}
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const innerSubscriber = new InnerSubscriber(this, undefined, undefined);
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const destination = this.destination;
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destination.add(innerSubscriber);
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this.innerSubscription = subscribeToResult(this, result, value, index, innerSubscriber);
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}
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_complete() {
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const { innerSubscription } = this;
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if (!innerSubscription || innerSubscription.closed) {
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super._complete();
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}
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this.unsubscribe();
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}
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_unsubscribe() {
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this.innerSubscription = null;
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}
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notifyComplete(innerSub) {
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const destination = this.destination;
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destination.remove(innerSub);
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this.innerSubscription = null;
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if (this.isStopped) {
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super._complete();
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}
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}
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notifyNext(outerValue, innerValue, outerIndex, innerIndex, innerSub) {
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this.destination.next(innerValue);
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}
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}
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//# sourceMappingURL=switchMap.js.map
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