[tz] [tz-announce] 2018f release of tz code and data available

[Steve Allen]

On Sat 2018-10-20T21:55:50+0100 Stephen Colebourne hath writ:
> The java.time.* code exposes the local time that the transition occurs.
> This can be represented within the bounds 00:00 to 24:00. There is no way
> to represent 25:00 or negatives.
> https://docs.oracle.com/javase/8/docs/api/java/time/zone/ZoneOffsetTransitionRule.html

Many examples of non-normalized dates and times exist in historical
literature.  One example is 1970 January -1 and December 35 at
https://babel.hathitrust.org/cgi/pt?id=mdp.39015017143895;view=1up;seq=30
The subsequent page has January -6 and December 40, and not to be
forgotten in other civil use was 1712 February 30
https://en.wikipedia.org/wiki/February_30

> As such, the tzdb parser would have to convert 25:00 and try to reinterpret
> it as the next day within the valid bounds, which is far from ideal. It
> would be much better for the upstream source to represent the data in a
> more standard and backwards compatible way.

People did these sorts of things, and not just in astronomy.  The
choice is whether or not a modern parser will be able to read what
people actually did or go into a mode resembling denial.

--
Steve Allen                    <sla at ucolick.org>              WGS-84 (GPS)
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