[tz] Dealing with Pre-1970 Data

Guy Harris guy at alum.mit.edu
Fri Aug 30 21:42:36 UTC 2013

On Aug 30, 2013, at 2:07 PM, Stephen Colebourne <scolebourne at joda.org> wrote:

> On 30 August 2013 21:10, Guy Harris <guy at alum.mit.edu> wrote:
>> If we're obliged to leave them in the tzdb for backwards compatibility purposes, we should:


>>        freeze them and devote no effort to updating them;
> -1. So long as we have them, there should be a best efforts attempt to
> maintain them. Realistically, that only means that any new zone should
> have an appropriate LMT set. No more.

-1.  *Maybe* we should keep the existing LMT values, but I emphatically do *NOT* believe that we should provide LMT for new tzids; we should not do *anything* that encourages people to think Gondwanaland/Argo_City somehow corresponds specifically to Argo City, rather than to a zone within a particular ISO 3166-named entity the currently-most-populated (undisputed) city of which happens to be Argo City.

> FWIW, I've started the process of removing LMT from Java JSR-310.
> Unfortunately, the option of throwing an error for far past values
> (back to the age of the universe) is not an option. I do understand
> the weirdness of these far past times, but in the context of the API
> it is simply not acceptable to have date-times in the 1700s for
> example without any notion of offset from GMT.

Then do it within the Java runtime library, perhaps using the tzdb for standard times and using Something Else prior to the availability of standard time at the location (perhaps just pretending that, prior to the establishment of standard time, the initial standard time offset was in place).

More information about the tz mailing list