28 lines
967 B
JavaScript
28 lines
967 B
JavaScript
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import { identity } from '../util/identity';
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import { operate } from '../util/lift';
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import { createOperatorSubscriber } from './OperatorSubscriber';
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export function skipLast(skipCount) {
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return skipCount <= 0
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?
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identity
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: operate((source, subscriber) => {
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let ring = new Array(skipCount);
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let seen = 0;
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source.subscribe(createOperatorSubscriber(subscriber, (value) => {
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const valueIndex = seen++;
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if (valueIndex < skipCount) {
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ring[valueIndex] = value;
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}
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else {
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const index = valueIndex % skipCount;
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const oldValue = ring[index];
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ring[index] = value;
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subscriber.next(oldValue);
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}
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}));
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return () => {
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ring = null;
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};
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});
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}
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//# sourceMappingURL=skipLast.js.map
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