/**
 * @typedef {Object} Difference Represents a difference between two given valid Unix time signatures
 * @property {?number} ms Total number of MS difference
 * @property {?number} days Number of days spanned
 * @property {?number} hours Number of hours spanned after higher units are subtracted
 * @property {?number} minutes Number of minutes spanned after higher units are subtracted
 * @property {?number} secs Number of seconds spanned after higher units are subtracted
 * @property {Function} toString() Returns duration formatted as `# days, # hours, # mins, # secs`
 * @property {Function} toSimplifiedString() Returns duration formatted as `#d #h #m #s`
 */
export declare type Difference = {
    ms?: number;
    days?: number;
    hours?: number;
    mins?: number;
    secs?: number;
    toString(): string;
    toSimplifiedString?(): string;
};