31 lines
1.2 KiB
JavaScript
31 lines
1.2 KiB
JavaScript
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import { operate } from '../util/lift';
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import { createOperatorSubscriber } from './OperatorSubscriber';
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import { innerFrom } from '../observable/innerFrom';
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import { identity } from '../util/identity';
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import { noop } from '../util/noop';
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import { popResultSelector } from '../util/args';
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export function withLatestFrom(...inputs) {
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const project = popResultSelector(inputs);
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return operate((source, subscriber) => {
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const len = inputs.length;
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const otherValues = new Array(len);
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let hasValue = inputs.map(() => false);
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let ready = false;
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for (let i = 0; i < len; i++) {
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innerFrom(inputs[i]).subscribe(createOperatorSubscriber(subscriber, (value) => {
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otherValues[i] = value;
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if (!ready && !hasValue[i]) {
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hasValue[i] = true;
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(ready = hasValue.every(identity)) && (hasValue = null);
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}
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}, noop));
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}
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source.subscribe(createOperatorSubscriber(subscriber, (value) => {
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if (ready) {
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const values = [value, ...otherValues];
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subscriber.next(project ? project(...values) : values);
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}
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}));
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});
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}
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//# sourceMappingURL=withLatestFrom.js.map
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