# File lib/ice_cube/validations/day_of_week.rb, line 61
      def build_ical(builder)
        ical_day = IcalBuilder.fixnum_to_ical_day(day)
        # Delete any with this day and no occ first
        builder['BYDAY'].delete_if { |d| d == ical_day }
        builder['BYDAY'] << "#{occ}#{ical_day}"
      end