1 | import { Subscriber } from '../Subscriber';
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2 | import { ArgumentOutOfRangeError } from '../util/ArgumentOutOfRangeError';
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3 | export function skipLast(count) {
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4 | return (source) => source.lift(new SkipLastOperator(count));
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5 | }
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6 | class SkipLastOperator {
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7 | constructor(_skipCount) {
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8 | this._skipCount = _skipCount;
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9 | if (this._skipCount < 0) {
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10 | throw new ArgumentOutOfRangeError;
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11 | }
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12 | }
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13 | call(subscriber, source) {
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14 | if (this._skipCount === 0) {
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15 | return source.subscribe(new Subscriber(subscriber));
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16 | }
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17 | else {
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18 | return source.subscribe(new SkipLastSubscriber(subscriber, this._skipCount));
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19 | }
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20 | }
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21 | }
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22 | class SkipLastSubscriber extends Subscriber {
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23 | constructor(destination, _skipCount) {
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24 | super(destination);
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25 | this._skipCount = _skipCount;
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26 | this._count = 0;
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27 | this._ring = new Array(_skipCount);
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28 | }
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29 | _next(value) {
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30 | const skipCount = this._skipCount;
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31 | const count = this._count++;
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32 | if (count < skipCount) {
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33 | this._ring[count] = value;
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34 | }
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35 | else {
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36 | const currentIndex = count % skipCount;
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37 | const ring = this._ring;
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38 | const oldValue = ring[currentIndex];
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39 | ring[currentIndex] = value;
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40 | this.destination.next(oldValue);
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41 | }
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42 | }
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43 | }
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44 | //# sourceMappingURL=skipLast.js.map |
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