/**
 * 是否为函数
 * @param obj
 */
export declare const isFunction: (obj: any) => boolean;
/**
 * 是否为全局对象
 * @param obj
 */
export declare const isWindow: (obj: any) => boolean;
/**
 * 是否为对象
 * @param obj
 */
export declare const isPlainObject: (obj: any) => boolean;
export declare const extend: (...args: any[]) => any;