import { I as IterableContainer } from './IterableContainer-CtfinwiH.js';

type Only<T extends IterableContainer> = T extends readonly [...Array<unknown>, unknown, unknown] | readonly [] | readonly [unknown, ...Array<unknown>, unknown] | readonly [unknown, unknown, ...Array<unknown>] ? undefined : T extends readonly [unknown] ? T[number] : T[number] | undefined;
/**
 * Returns the first and only element of `array`, or undefined otherwise.
 *
 * @param array - The target array.
 * @signature
 *    R.only(array)
 * @example
 *    R.only([]) // => undefined
 *    R.only([1]) // => 1
 *    R.only([1, 2]) // => undefined
 * @dataFirst
 * @category Array
 */
declare function only<T extends IterableContainer>(array: Readonly<T>): Only<T>;
/**
 * Returns the first and only element of `array`, or undefined otherwise.
 *
 * @signature
 *    R.only()(array)
 * @example
 *    R.pipe([], R.only()); // => undefined
 *    R.pipe([1], R.only()); // => 1
 *    R.pipe([1, 2], R.only()); // => undefined
 * @dataLast
 * @category Array
 */
declare function only<T extends IterableContainer>(): (array: Readonly<T>) => Only<T>;

export { only };