text: export function hdel(key, ...fields) {
    const value = this.data.get(key);
    const numDeleted = fields.filter(field => {
      if ({}.hasOwnProperty.call(value, field)) {
        delete value[field];
        return true;
      }
      return false;
    }).length;
    this.data.set(key, value);
    return numDeleted;
  }
  