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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
/** * Merge multiple streams into a single one, taking order into account, and each stream * will wait for a chunk to enqueue before the next stream can append another chunk. * If a stream ends before other ones, the others will continue adding data in order, * and the finished one will not add any more data. */export function zipReadableStreams<T>(  ...streams: ReadableStream<T>[]): ReadableStream<T> {  const readers = streams.map((s) => s.getReader());  return new ReadableStream<T>({    async start(controller) {      try {        let resolved = 0;        while (resolved != streams.length) {          for (const [key, reader] of Object.entries(readers)) {            const { value, done } = await reader.read();            if (!done) {              controller.enqueue(value!);            } else {              resolved++;              readers.splice(+key, 1);            }          }        }        controller.close();      } catch (e) {        controller.error(e);      }    },  });}