export declare function is(val: unknown, type: string): boolean; export declare function isDef(val?: T): val is T; export declare function isUnDef(val?: T): val is T; export declare function isObject(val: any): val is Record; export declare function isNotEmpty(val: any): boolean; export declare function isEmpty(val: T): val is T; export declare function isDate(val: unknown): val is Date; export declare function isNull(val: unknown): val is null; export declare function isNullAndUnDef(val: unknown): val is null | undefined; export declare function isNullOrUnDef(val: unknown): val is null | undefined; export declare function isNumber(val: unknown): val is number; export declare function isPromise(val: unknown): val is Promise; export declare function isString(val: unknown): val is string; export declare function isFunction(val: unknown): val is Function; export declare function isBoolean(val: unknown): val is boolean; export declare function isRegExp(val: unknown): val is RegExp; export declare function isArray(val: any): val is Array; export declare function isWindow(val: any): val is Window; export declare function isElement(val: unknown): val is Element; export declare function isMap(val: unknown): val is Map; export declare const isServer: boolean; export declare const isClient: boolean; export declare function isUrl(path: string): boolean;