Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com> writes:
> Haven't had time to work through what the above is actually doing.
I think the first two are explained by 489c9c340:
Also, arrange for the combination of a negative year and an
explicit "BC" marker to cancel out and produce AD. This is how
the negative-century case works, so it seems sane to do likewise.
The last two look like a parsing issue: with no field separator
(nope, the space doesn't count), the code is taking the dash
as a field separator.
regards, tom lane