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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
/** * 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. * * @example * ```ts * import { zipReadableStreams } from "https://deno.land/std@$STD_VERSION/streams/zip_readable_streams.ts"; * * const stream1 = ReadableStream.from(["1", "2", "3"]); * const stream2 = ReadableStream.from(["a", "b", "c"]); * const zippedStream = zipReadableStreams(stream1, stream2); * * await Array.fromAsync(zippedStream); // ["1", "a", "2", "b", "3", "c"]; * ``` */export function zipReadableStreams<T>(  ...streams: ReadableStream<T>[]): ReadableStream<T> {  const readers = new Set(streams.map((s) => s.getReader()));  return new ReadableStream<T>({    async start(controller) {      try {        let resolved = 0;        while (resolved !== streams.length) {          for (const reader of readers) {            const { value, done } = await reader.read();            if (!done) {              controller.enqueue(value!);            } else {              resolved++;              readers.delete(reader);            }          }        }        controller.close();      } catch (e) {        controller.error(e);      }    },  });}