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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
import { deferred } from "../async/deferred.ts";
/** * Merge multiple streams into a single one, not taking order into account. * If a stream ends before other ones, the other will continue adding data, * and the finished one will not add any more data. */export function mergeReadableStreams<T>(  ...streams: ReadableStream<T>[]): ReadableStream<T> {  const resolvePromises = streams.map(() => deferred<void>());  return new ReadableStream<T>({    start(controller) {      let mustClose = false;      Promise.all(resolvePromises)        .then(() => {          controller.close();        })        .catch((error) => {          mustClose = true;          controller.error(error);        });      for (const [key, stream] of Object.entries(streams)) {        (async () => {          try {            for await (const data of stream) {              if (mustClose) {                break;              }              controller.enqueue(data);            }            resolvePromises[+key].resolve();          } catch (error) {            resolvePromises[+key].reject(error);          }        })();      }    },  });}