44 lines
1.3 KiB
Plaintext
44 lines
1.3 KiB
Plaintext
import { Subscriber } from '../Subscriber';
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import { ArgumentOutOfRangeError } from '../util/ArgumentOutOfRangeError';
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export function skipLast(count) {
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return (source) => source.lift(new SkipLastOperator(count));
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}
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class SkipLastOperator {
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constructor(_skipCount) {
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this._skipCount = _skipCount;
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if (this._skipCount < 0) {
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throw new ArgumentOutOfRangeError;
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}
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}
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call(subscriber, source) {
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if (this._skipCount === 0) {
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return source.subscribe(new Subscriber(subscriber));
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}
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else {
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return source.subscribe(new SkipLastSubscriber(subscriber, this._skipCount));
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}
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}
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}
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class SkipLastSubscriber extends Subscriber {
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constructor(destination, _skipCount) {
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super(destination);
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this._skipCount = _skipCount;
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this._count = 0;
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this._ring = new Array(_skipCount);
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}
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_next(value) {
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const skipCount = this._skipCount;
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const count = this._count++;
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if (count < skipCount) {
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this._ring[count] = value;
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}
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else {
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const currentIndex = count % skipCount;
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const ring = this._ring;
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const oldValue = ring[currentIndex];
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ring[currentIndex] = value;
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this.destination.next(oldValue);
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}
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}
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}
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//# sourceMappingURL=skipLast.js.map |