Method strings

lib/encoding/xml.ts:65–89

(opts: {
    required?: R,
    optional?: O,
  })

  }

  strings<
    R extends {[key: string]: true},
    O extends {[key: string]: true},
  >(opts: {
    required?: R,
    optional?: O,
  }): { [key in keyof R]: string }
    & { [key in keyof O]: string | undefined }
  {
    const required: Array<keyof R> = Object.keys(opts.required ?? {});
    const optional: Array<keyof O> = Object.keys(opts.optional ?? {});
    type T = keyof R | keyof O;

    const obj = Object.create(null);
    const missing = new Set(required);
    const strings: Set<T> = new Set(new Array<keyof O|keyof R>().concat(required, optional));
    for (const child of this.children) {
      if (strings.has(child.name)) {
        obj[child.name as T] = child.content ?? '';
        missing.delete(child.name);
      }
    }
    if (missing.size > 0) this.throwMissingKeys(missing);
    return obj;
  }

  throwMissingKeys(missingKeys: Iterable<string|number|symbol>): never {
    throw new Error(`BUG: XmlNode ${JSON.stringify(this.name)