service_object.rb

class Email::Validate
  def self.call(email)
    new(email, RFC::CheckSyntaxt, SMTP::CheckUserExistance).call
  end

  attr_reader :email, :rfc_check_syntaxt, :smtp_check_user

  def initialize(email, rfc_check_syntaxt, smtp_check_user)
    @email = email
    @rfc_check_syntaxt = rfc_check_syntaxt
    @smtp_check_user = smtp_check_user
  end

  def call
    rfc_check_syntaxt.call(email)
    smtp_check_user.call(email)
  end
end

# Usage
begin
  Email::Validate.call("malformed@emailcom")
  puts "Valid email address"
rescue EmailSyntaxtError, SMTP::NonExistentUserError
 puts "Invalid email address"
end