import { ValidationOptions } from 'class-validator';
export declare const IS_ISO6391 = "isISO6391";
/**
 * Check if the string is a valid [ISO 639-1](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2)
 * officially assigned country code.
 */
export declare function isISO6391(value: unknown): boolean;
/**
 * Check if the string is a valid [ISO 3166-1](https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes) official code.
 */
export declare function IsISO6391(validationOptions?: ValidationOptions): PropertyDecorator;
export declare function isISO6391Validator(value: string): boolean;