/**
 * **Standard :** RFC 1035
 *
 * @see https://datatracker.ietf.org/doc/html/rfc1035#section-2.3.1
 *
 * **Follows :**
 * `<domain>`
 *
 * @version 1.0.0-beta
 */
export declare function isDomain(str: string, params?: undefined): boolean;