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30 lines
914 B
30 lines
914 B
4 years ago
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import { Subscriber } from '../Subscriber';
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export function defaultIfEmpty(defaultValue = null) {
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return (source) => source.lift(new DefaultIfEmptyOperator(defaultValue));
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}
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class DefaultIfEmptyOperator {
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constructor(defaultValue) {
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this.defaultValue = defaultValue;
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}
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call(subscriber, source) {
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return source.subscribe(new DefaultIfEmptySubscriber(subscriber, this.defaultValue));
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}
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}
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class DefaultIfEmptySubscriber extends Subscriber {
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constructor(destination, defaultValue) {
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super(destination);
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this.defaultValue = defaultValue;
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this.isEmpty = true;
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}
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_next(value) {
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this.isEmpty = false;
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this.destination.next(value);
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}
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_complete() {
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if (this.isEmpty) {
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this.destination.next(this.defaultValue);
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}
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this.destination.complete();
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}
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}
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//# sourceMappingURL=defaultIfEmpty.js.map
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