type EmailOptions = {
    allowDisplayName: boolean;
    allowUnderscores: boolean;
    requireDisplayName: boolean;
    allowUtf8LocalPart: boolean;
    requireTld: boolean;
    blacklistedChars: string;
    /**
     * Email should not be longer then 254 chars.
     * If you want to allow longer email, set this setting to `true`
     * @default false
     */
    ignoreMaxLength: boolean;
    hostBlacklist: string[];
    hostWhitelist: string[];
    domainSpecificValidation: boolean;
    allowIpDomain: boolean;
};
export declare function isEmail(str: string, userOptions: Partial<EmailOptions>): boolean;
export {};