import { type NotUndefined, type Undefinable } from '../core/undefinable.js';
/**
 *  Return _input_ as `T` if the passed _input_ is not `undefined`.
 *  Otherwise, return _defaultValue_.
 *
 *  * _defaultValue_ must not be `Undefinable<*>`.
 *  * If the result of _defaultValue_ is `undefined`, throw `TypeError`.
 */
export declare function unwrapOrForUndefinable<T>(input: Undefinable<T>, defaultValue: NotUndefined<T>): NotUndefined<T>;