29 lines
723 B
JavaScript
29 lines
723 B
JavaScript
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import { Subscriber } from '../Subscriber';
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export function pairwise() {
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return (source) => source.lift(new PairwiseOperator());
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}
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class PairwiseOperator {
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call(subscriber, source) {
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return source.subscribe(new PairwiseSubscriber(subscriber));
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}
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}
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class PairwiseSubscriber extends Subscriber {
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constructor(destination) {
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super(destination);
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this.hasPrev = false;
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}
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_next(value) {
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let pair;
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if (this.hasPrev) {
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pair = [this.prev, value];
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}
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else {
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this.hasPrev = true;
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}
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this.prev = value;
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if (pair) {
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this.destination.next(pair);
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}
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}
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}
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//# sourceMappingURL=pairwise.js.map
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