[tz] Adding verified historic details

[Stephen Colebourne]

On 4 September 2013 21:53, Paul Eggert <eggert at cs.ucla.edu> wrote:
> On 09/04/13 13:43, Lester Caine wrote:
>> Is that good enough to merge?
>
> I'm afraid we can't add zones that differ only in pre-1970
> dates until we can figure out how to filter them out in
> the default case, as we aren't prepared for the
> hundreds or thousands of new zones that would be feasible
> if we opened the floodgates.  Zefram has one prototype for
> filtering, which I really must get to at some point.

The Isle of Man is already in the main tzdb, so no new ID is being
created and nothing changes for the selection code. Changing a Link to
a Zone because more data is now available is perfectly reasonable and
must not be a blocker here.

Were there a request to create a new zone ID that is not currently
present that would be an entirely different matter.

Stephen