# File lib/ice_cube/validations/monthly_interval.rb, line 5
    def interval(interval)
      interval = normalized_interval(interval)
      verify_alignment(interval, :month, :interval) { |error| raise error }

      @interval = interval
      replace_validations_for(:interval, [Validation.new(@interval)])
      clobber_base_validations(:month)
      self
    end