/**
 * Generates a unique identifier.
 *
 * @param initialValue Optional initial value for the ID.
 * @returns The generated or provided ID.
 *
 * @example
 * ```tsx
 * const id = useId('foo');
 * console.log(id); // 'foo'
 * ```
 *
 * @example
 * ```tsx
 * const defaultId = useId();
 * console.log(defaultId); // e.g., 'pr_id_0'
 * ```
 */
export declare function useId(initialValue?: string): string;