/**
 * Adds the given number of days to the given date and returns a new Date object.
 *
 * @deprecated Use {@link shiftDays} instead.
 */
export declare function addDays(days: number, date?: Date | string | number): Date;
/**
 * Shifts the given date by a specified number of days and returns a new Date object.
 *
 * Can take both positive and negative values for days.
 *
 * @param {number} days - The number of days to add to the date.
 * @param {Date} [date=new Date()] - The date to add the days to. Defaults to the current date.
 * @returns {Date} - A new Date object with the given number of days added.
 */
export declare function shiftDays(days: number, date?: Date | string | number): Date;