export declare const isString: (value: unknown) => value is string; export declare const isStringFull: (value: string) => boolean; export declare const isEmptyString: (value: string) => boolean; export declare const isNull: (value: unknown) => value is null; export declare const isUndefined: (value: unknown) => value is undefined; export declare const isNil: (value: T) => value is Extract; export declare const isDefined: (value: T) => value is Exclude; export declare const isObject: (value: T) => value is Extract; export declare const isObjectFull: (value: object) => boolean; export declare const isEmptyObject: (value: object) => boolean; export declare const isArray: (value: T) => value is Extract; export declare const isArrayFull: (value: unknown[]) => boolean; export declare const isEmptyArray: (value: unknown[]) => boolean;