[tz] attic data for the tz database

[Paul Eggert]

On 08/29/2013 12:33 PM, Stephen Colebourne wrote:

> You need to explain how the pre-1970 data that we do have will be
> retained and accessible.

Yes, that's the goal.  I expect the code is what's needed next, and it
should help explain things.  I plan to write it soon.

> the users I represent don't care about the accuracy, but
> they will care if it is made willfully inaccurate.

I'm afraid I don't follow.  As we've seen, similar changes have been
made to the tz database regularly, and evidently those users didn't
notice or care.  What's different about these changes?

> A comprehensive solution might be two sets of files, one pre and one
> post 1970 with enough notice for everyone to be able to adapt.

Yes, though I'm hoping we can be a bit more flexible, with settable
cutoff dates, something along the lines that Zefram suggested.

> I want to ensure that we don't see a release from the current set of
commits.

The current experimental version will definitely not be released
as-is, so please don't worry about that.