51 lines
1.7 KiB
JavaScript
51 lines
1.7 KiB
JavaScript
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import { Subscriber } from '../Subscriber';
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export function find(predicate, thisArg) {
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if (typeof predicate !== 'function') {
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throw new TypeError('predicate is not a function');
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}
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return (source) => source.lift(new FindValueOperator(predicate, source, false, thisArg));
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}
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export class FindValueOperator {
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constructor(predicate, source, yieldIndex, thisArg) {
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this.predicate = predicate;
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this.source = source;
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this.yieldIndex = yieldIndex;
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this.thisArg = thisArg;
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}
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call(observer, source) {
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return source.subscribe(new FindValueSubscriber(observer, this.predicate, this.source, this.yieldIndex, this.thisArg));
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}
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}
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export class FindValueSubscriber extends Subscriber {
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constructor(destination, predicate, source, yieldIndex, thisArg) {
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super(destination);
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this.predicate = predicate;
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this.source = source;
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this.yieldIndex = yieldIndex;
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this.thisArg = thisArg;
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this.index = 0;
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}
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notifyComplete(value) {
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const destination = this.destination;
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destination.next(value);
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destination.complete();
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this.unsubscribe();
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}
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_next(value) {
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const { predicate, thisArg } = this;
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const index = this.index++;
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try {
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const result = predicate.call(thisArg || this, value, index, this.source);
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if (result) {
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this.notifyComplete(this.yieldIndex ? index : value);
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}
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}
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catch (err) {
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this.destination.error(err);
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}
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}
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_complete() {
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this.notifyComplete(this.yieldIndex ? -1 : undefined);
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}
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}
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//# sourceMappingURL=find.js.map
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