1 | import { Subscriber } from '../Subscriber';
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2 | export function scan(accumulator, seed) {
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3 | let hasSeed = false;
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4 | if (arguments.length >= 2) {
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5 | hasSeed = true;
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6 | }
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7 | return function scanOperatorFunction(source) {
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8 | return source.lift(new ScanOperator(accumulator, seed, hasSeed));
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9 | };
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10 | }
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11 | class ScanOperator {
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12 | constructor(accumulator, seed, hasSeed = false) {
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13 | this.accumulator = accumulator;
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14 | this.seed = seed;
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15 | this.hasSeed = hasSeed;
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16 | }
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17 | call(subscriber, source) {
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18 | return source.subscribe(new ScanSubscriber(subscriber, this.accumulator, this.seed, this.hasSeed));
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19 | }
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20 | }
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21 | class ScanSubscriber extends Subscriber {
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22 | constructor(destination, accumulator, _seed, hasSeed) {
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23 | super(destination);
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24 | this.accumulator = accumulator;
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25 | this._seed = _seed;
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26 | this.hasSeed = hasSeed;
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27 | this.index = 0;
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28 | }
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29 | get seed() {
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30 | return this._seed;
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31 | }
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32 | set seed(value) {
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33 | this.hasSeed = true;
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34 | this._seed = value;
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35 | }
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36 | _next(value) {
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37 | if (!this.hasSeed) {
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38 | this.seed = value;
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39 | this.destination.next(value);
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40 | }
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41 | else {
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42 | return this._tryNext(value);
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43 | }
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44 | }
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45 | _tryNext(value) {
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46 | const index = this.index++;
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47 | let result;
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48 | try {
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49 | result = this.accumulator(this.seed, value, index);
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50 | }
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51 | catch (err) {
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52 | this.destination.error(err);
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53 | }
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54 | this.seed = result;
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55 | this.destination.next(result);
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56 | }
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57 | }
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58 | //# sourceMappingURL=scan.js.map |
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