@reactivex/ix-esnext-esm
Version:
The Interactive Extensions for JavaScript
45 lines (43 loc) • 1.6 kB
JavaScript
import { AsyncIterableX } from './asynciterablex';
import { wrapWithAbort } from './operators/withabort';
import { throwIfAborted } from '../aborterror';
// eslint-disable-next-line @typescript-eslint/no-empty-function
const NEVER_PROMISE = new Promise(() => { });
function wrapPromiseWithIndex(promise, index) {
return promise.then((value) => ({ value, index }));
}
export class MergeAsyncIterable extends AsyncIterableX {
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 = Promise.race(nexts);
const { value: { done: done$, value: value$ }, index, } = await next;
if (done$) {
nexts[index] = NEVER_PROMISE;
active--;
}
else {
const iterator$ = iterators[index];
nexts[index] = wrapPromiseWithIndex(iterator$.next(), index);
yield value$;
}
}
}
}
export function merge(source, ...args) {
return new MergeAsyncIterable([source, ...args]);
}
//# sourceMappingURL=merge.mjs.map