export declare const EmailRegExp: RegExp;
export declare const PhoneRegExp: RegExp;
export declare const PhoneE164Exp: RegExp;
export declare function isValidEmail(email?: string): string | undefined;
export declare function isPhoneValid(phone: string, regionCode: string): boolean;
export declare const isValidE164PhoneNumber: (phone: string | undefined) => string | undefined;
export declare function isValidCaptcha(code?: string): "" | RegExpMatchArray | null | undefined;