/**
 * Generates a unique ID. If `prefix` is given, the ID is appended to it.
 *
 * @since 5.12.0
 * @category Util
 * @param prefix The value to prefix the ID with.
 * @returns Returns the unique ID.
 * @see [[random]]
 * @example
 *
 * ```js
 * uniqueId('contact_')
 * // => 'contact_104'
 *
 * uniqueId()
 * // => '105'
 * ```
 */
export declare function uniqueId(prefix?: string): string;
export default uniqueId;