Dave: If I understand you correctly, your module is using "Calendrical Calculations" as an "algorithmic bible" because the LISP code is so amenable to Perl conversion. They are not the only calendric gospel around. Can you accomodate either case with flags/switches?
I assert, rhetorically perhaps, that historical projection of a proleptic Gregorian calendar is of such limited value because (IMO) most if not all published literature has not and will not in our life times normalize their date reckoning to any universal calendar (like Star Date a la Star Trek). 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. 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. Since most astronomers use the Julian Date System (JD numbers) a proleptic Gregorian with year zero doesn't help them either. Enough said. I'm done with this topic, unless provoked or simulated otherwise <g>. Larry FYI: "Herod the Great:" Roman king of Judea (37 BC to 4 AD) that was 40 years not 41 years! Dave Rolsky wrote: > On Wed, 26 Feb 2003, Lawrence K. Hixson wrote: > > > I found the reference on the web to this question which I believe adds > > weight to Abigail's assertion: > > > > http://aa.usno.navy.mil/faq/docs/millennium.html > > > > Be sure to read last paragraph at link above! > > But in chapter 2 of Calendrical Calculations, they say: > > Although the Gregorian calendar did not exist priot to the sixteenth > century, we can extrapolate backwrads using its rules to obtain what is > sometimes referred to the as the "proleptic Gregorian calendar," which we > implement in the next section. Unlike the Julian calendar, this > proleptic calendar _does_ have a year 0. > > They then go on to define the epoch of the Gregorian calendar as year 1, > meaning -1 BC is year 0. That's what DateTime.pm does too. > > -dave > > /*======================= > House Absolute Consulting > www.houseabsolute.com > =======================*/
