EXRULEs, RDATEs and EXDATEs

[deflatermouse]

Implemented support for the above in Data::ICal::DateTime which means that given this bit of iCalendar

BEGIN:VCALENDAR BEGIN:VEVENT DTSTART;TZID=Europe/London:20050804T183000 DTEND;TZID=Europe/London:20050804T230000 SUMMARY:London.pm social UID:6700873C-0409-11DA-A793-000A9599EB44 SEQUENCE:7 DTSTAMP:20050803T102748Z RRULE:FREQ=MONTHLY;INTERVAL=1;BYDAY=1TH RRULE:FREQ=MONTHLY;INTERVAL=1;BYDAY=TH;BYMONTHDAY=8 EXRULE:FREQ=MONTHLY;INTERVAL=1;BYDAY=TH;BYMONTHDAY=1 DESCRIPTION:We get drunk and talk crap END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/London:20050804T183000 DTEND;TZID=Europe/London:20050804T230000 SUMMARY:London.pm Heretics social UID:6700873C-0409-11DA-A793-000A9599EB44 SEQUENCE:7 DTSTAMP:20050803T102748Z RRULE:FREQ=MONTHLY;INTERVAL=1;BYDAY=TH;BYMONTHDAY=1 DESCRIPTION:We get *really* drunk and talk crap END:VEVENT END:VCALENDAR
we can now generate the correct sequence of events for London.pm's hideously complicated meeting schedule.