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// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.type Writer = Deno.Writer;type WriterSync = Deno.WriterSync;
const decoder = new TextDecoder();
/** Writer utility for buffering string chunks */export class StringWriter implements Writer, WriterSync {  private chunks: Uint8Array[] = [];  private byteLength = 0;  private cache: string | undefined;
  constructor(private base: string = "") {    const c = new TextEncoder().encode(base);    this.chunks.push(c);    this.byteLength += c.byteLength;  }
  write(p: Uint8Array): Promise<number> {    return Promise.resolve(this.writeSync(p));  }
  writeSync(p: Uint8Array): number {    this.chunks.push(p);    this.byteLength += p.byteLength;    this.cache = undefined;    return p.byteLength;  }
  toString(): string {    if (this.cache) {      return this.cache;    }    const buf = new Uint8Array(this.byteLength);    let offs = 0;    for (const chunk of this.chunks) {      buf.set(chunk, offs);      offs += chunk.byteLength;    }    this.cache = decoder.decode(buf);    return this.cache;  }}