On Fri, 26 Sep 2003, Flavio S. Glock wrote: > Dave Rolsky wrote: > > > > On Fri, 26 Sep 2003, Flavio S. Glock wrote: > > > > > I think this is wrong, because the RD day is an absolute > > > time and should only change at "midnight", whatever > > > calendar module you use. > > > > > > year/month/day should change, but RD must stay synchronized > > > with DateTime. > > > > Yes. Anything else is broken behavior. We should probably add this to > > the calendar module dev docs. How should it be phrased? > > How about: > > http://datetime.perl.org/developer/calendar.html > > Converting Between Calendars > > [...] > Rata Die datetimes follow the UTC timescale. > Even in calendars in which the day changes at sunset, > the RD day still changes at midnight.
I added this to the calendar docs. > Event Calculations > > Modules that calculate events should return results > using the same class, time zone and locale as the > argument: > > $dt2 = $eclipse->next( $dt1 ); > > The easiest way to implement this is to calculate a > DateTime::Duration, and then return > C<argument + duration>. > > Note that if you feed a floating time to a module > that makes calculations using UTC, the result > will be a floating time that is only valid in > the UTC time zone. Most astronomical calculations > are in this category, such as sunrise, sunset, > and moon position. I made a new document for DateTime::Event modules with this text. -dave /*======================= House Absolute Consulting www.houseabsolute.com =======================*/
