resquest.rb

module Validations

  @catch_next_method = false

  def validate(*validations)
    @validations = validations
    @catch_next_method = true
  end

  def method_added(method_name)
    if @catch_next_method then
      @catch_next_method = false
      alias_method :"_#{method_name.to_s}", method_name
      ###Hacer algo
    end
  end

end

#Ejemplo
class StatusRequestType
  extend Validations
  
  validate :registration

  def fulfill_for(user, request)
    Bot.send_to(user.id, "#{user.subscribed ? 'Te' : 'No te'} encontrás suscripto")
  end

end