43 lines
1.1 KiB
JavaScript
43 lines
1.1 KiB
JavaScript
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import { Subscriber } from '../Subscriber';
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import { ArgumentOutOfRangeError } from '../util/ArgumentOutOfRangeError';
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import { empty } from '../observable/empty';
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export function take(count) {
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return (source) => {
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if (count === 0) {
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return empty();
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}
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else {
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return source.lift(new TakeOperator(count));
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}
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};
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}
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class TakeOperator {
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constructor(total) {
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this.total = total;
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if (this.total < 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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return source.subscribe(new TakeSubscriber(subscriber, this.total));
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}
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}
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class TakeSubscriber extends Subscriber {
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constructor(destination, total) {
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super(destination);
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this.total = total;
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this.count = 0;
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}
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_next(value) {
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const total = this.total;
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const count = ++this.count;
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if (count <= total) {
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this.destination.next(value);
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if (count === total) {
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this.destination.complete();
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this.unsubscribe();
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}
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}
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}
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}
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//# sourceMappingURL=take.js.map
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