export declare const isEmpty: (value: unknown) => value is null | undefined; export declare const isNotEmpty: (value: T | null | undefined) => value is T; export declare const isNumber: (value: unknown) => value is number; export declare const isInt: (value: unknown) => value is number; export declare const isStr: (value: unknown) => value is string; export declare const isAnObj: (value: unknown) => value is T; export declare const isATuple: (value: unknown) => value is T; export declare const isBool: (value: unknown) => value is boolean;