/** 已经声明/定义的数据 */
export declare function isDef<T>(val: T): val is NonNullable<T>;
/** 是数组 */
export declare const isArray: <T>(v: unknown) => v is T[];
export declare const isNumber: <T = number>(v: unknown) => v is T;
/** 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;
/** 是一个 Promise */
export declare const isPromise: <T = any>(val: any) => val is Promise<T>;
/** 是手机号码 */
export declare function isMobile(value: string): boolean;
/** 是空 */
export declare const isNullish: (value: any) => boolean;
export declare const isString: (value: any) => value is string;