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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
/** A TransformStream that will only read & enqueue `size` amount of chunks. * * if options.error is set, then instead of terminating the stream, * an error will be thrown. * * ```ts * import { LimitedTransformStream } from "https://deno.land/std@$STD_VERSION/streams/limited_transform_stream.ts"; * const res = await fetch("https://example.com"); * const parts = res.body!.pipeThrough(new LimitedTransformStream(50)); * ``` */export class LimitedTransformStream<T> extends TransformStream<T, T> {  #read = 0;  constructor(size: number, options: { error?: boolean } = {}) {    super({      transform: (chunk, controller) => {        if ((this.#read + 1) > size) {          if (options.error) {            throw new RangeError(`Exceeded chunk limit of '${size}'`);          } else {            controller.terminate();          }        } else {          this.#read++;          controller.enqueue(chunk);        }      },    });  }}