Lawrence K. Hixson schreef: > Most if not all extant manuscripts use the date reckoning most familiar to the > author's own method be it dynastic, Year # of Herod's rule, Julian, or > Gregorian depending upon circa. Even the Gregorian acceptance also varied by > country/prov/state by date as well.
But these will all(?) be implemented as DateTime::Calendars. I'm working on the Julian calendar and the several Julian/Gregorian calendars myself. > My final assertion is this: since the Gregorian Calendar functions as our > "civil calendar" today comparable to the Julian Calendar did before it AND > since the Julian doesn't recognize year zero, a proleptic Gregorian should not > accept it either. On the other hand, it's not entirely correct to have -1 mean 1 BC. This would lead one to think that BC and AD is one calendar, while they are in fact two different but related calendars. Besides, both the Julian and the Gregorian proleptic calendars are theoretical constructs, not used in the year 0 itself. So you can decide for yourself how you treat it. For my DT::Cal::Julian module, I've chosen to include a year 0 too, for consistency. (I would have prefered not to, but Dave is in charge...) > Since most astronomers use the Julian Date System (JD numbers) a proleptic > Gregorian with year zero doesn't help them either. Whether it helps them or no, they do use a zero-based year. Eugene
