/**
 * Returns the first element of an array or `undefined` if the array is empty.
 *
 * This function takes an array and returns the first element of the array.
 * If the array is empty, the function returns `undefined`.
 *
 * @template T - The type of elements in the array.
 * @param {ArrayLike<T> | undefined | null} arr - The array from which to get the first element.
 * @returns {T | undefined} The first element of the array, or `undefined` if the array is empty.
 *
 * @example
 * const emptyArr: number[] = [];
 * const noElement = head(emptyArr);
 * // noElement will be undefined
 */
declare function head<T>(arr: ArrayLike<T> | undefined | null): T | undefined;

export { head };