You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: form_add_email_validator.rb
    path of file: ./repos/identity-idp/app/validators
    
    the code of the file until where you have to start completion: module FormAddEmailValidator
  extend ActiveSupport::Concern

  included do
    include ActiveModel::Validations::Cal
    
  def validate_domain
    return unless email.present? && errors.blank?
    domain = Mail::Address.new(email).domain

    if domain && !domain.ascii_only?
      errors.add(:email, t('valid_email.validations.email.invalid'), type: :domain)
    end
  rescue Mail::Field::IncompleteParseError
    errors.add(:email, t('valid_email.validations.email.invalid'), type: :domain)
  end