/**
 * Get a Date object as UTC date string .
 * ex: 2019 09 01
 * @private
 */
export declare const getUTCDateString: (now?: Date) => string;
/**
 * Get the UTC time string of Date object.
 * ex: 09:05:01.123
 * @private
 */
export declare const getUTCTimeString: (date: Date) => string;
/**
 * Returns a string representation of a number, with a zero if the number is lower than 10.
 * @private
 */
export declare const pad: (integer: number) => string;
/**
 * Returns a 'hh:mm' string from a time in ms.
 * @param {Number} timeInMs Time in milliseconds.
 * @private
 */
export declare const getHoursAndMinutes: (timeInMs: number) => string;