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@reactivex/ix-esnext-esm

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The Interactive Extensions for JavaScript

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import { AsyncIterableX } from './asynciterablex.js'; import { wrapWithAbort } from './operators/withabort.js'; import { throwIfAborted } from '../aborterror.js'; import { safeRace } from '../util/safeRace.js'; // eslint-disable-next-line @typescript-eslint/no-empty-function const NEVER_PROMISE = new Promise(() => { }); function wrapPromiseWithIndex(promise, index) { return promise .then(({ value, done }) => ({ value, done, index })) .catch((error) => ({ error, index })); } /** @ignore */ export class MergeAsyncIterable extends AsyncIterableX { _source; constructor(source) { super(); this._source = source; } async *[Symbol.asyncIterator](signal) { throwIfAborted(signal); const length = this._source.length; const iterators = new Array(length); const nexts = new Array(length); let active = length; for (let i = 0; i < length; i++) { const iterator = wrapWithAbort(this._source[i], signal)[Symbol.asyncIterator](); iterators[i] = iterator; nexts[i] = wrapPromiseWithIndex(iterator.next(), i); } while (active > 0) { const next = await safeRace(nexts); if (next.hasOwnProperty('error')) { throw next.error; } else if (next.done) { nexts[next.index] = NEVER_PROMISE; active--; } else { const iterator$ = iterators[next.index]; nexts[next.index] = wrapPromiseWithIndex(iterator$.next(), next.index); yield next.value; } } } } export function merge(source, ...args) { return new MergeAsyncIterable([source, ...args]); } //# sourceMappingURL=merge.js.map