/**
 * @file Utility functions for domain and hostname validation.
 */
/**
 * Marker for a wildcard top-level domain — `.*`.
 *
 * @example
 * `example.*` — matches with any TLD, e.g. `example.org`, `example.com`, etc.
 */
export declare const WILDCARD_TLD: string;
/**
 * Marker for a wildcard subdomain — `*.`.
 *
 * @example
 * `*.example.org` — matches with any subdomain, e.g. `foo.example.org` or `bar.example.org`
 */
export declare const WILDCARD_SUBDOMAIN: string;
/**
 * Utility functions for domain and hostname validation.
 */
export declare class DomainUtils {
    /**
     * Check if the input is a valid domain or hostname.
     *
     * @param domain Domain to check
     * @returns `true` if the domain is valid, `false` otherwise
     */
    static isValidDomainOrHostname(domain: string): boolean;
}