/**
 * Adds a leading zero to a value if the value is less than 10
 *
 * @since v1.9.0
 * @category String
 * @param {string | number} value The original value to possibly add a leading zero
 * @returns {string}
 * @example
 * leadingZero(7)
 * //=> '07'
 *
 * leadingZero(10)
 * //=> '10'
 */
export declare const leadingZero: (value: string | number) => string;