/** 是对象 */
export declare const isObject: <T>(v: T) => v is T;
/** 是函数 */
export declare const isFunction: (v: any) => v is Function;
/** 是时间对象 */
export declare const isDate: <T>(v: T) => v is T;
/** 是一个 Promise */
export declare const isPromise: <T = any>(val: any) => val is Promise<T>;
/** 是空 */
export declare function isNullish(value: any): boolean;