/**
 *
 * This file may have been modified by Bytedance Inc. (“Bytedance Inc.'s Modifications”). 
 * All Bytedance Inc.'s Modifications are Copyright (year) Bytedance Inc..  
 * 
 * This source code is licensed under the Apache license.
 * See LICENSE file in the project root for license information.
 *
 */
export declare const isNumber: (value: unknown) => value is number;
export interface Options {
    leftTime?: number;
    targetDate?: number;
    interval?: number;
    onEnd?: () => void;
}
export interface FormattedRes {
    days: number;
    hours: number;
    minutes: number;
    seconds: number;
    milliseconds: number;
}
declare const useCountdown: (options?: Options) => readonly [number, FormattedRes];
export default useCountdown;