On 2017-12-08 08:26, Zefram wrote:
That's not a change to the format that zic accepts.
Well, I did not mean the input accepted by any particular implementation of zic but the public interface described in zic(8), the definition of the format of tzdb data. If some zic implementation accepts complex numbers as SAVE values that does not mean we can use it in tzdb data.
zic already does allow negative AT times.
Interesting. Allowing negative AT values would provide a "convenient notation" to avoid the Chatham Rules, as in Rule NZ 2008 max - Apr Sun>=1 -10:00u 0 S
zic.8 ought to be patched to make explicit that AT and SAVE have no small range limits.
Yes, and it may also be necessary to state the meaning of such extensions; for instance, the suffixes u, g, z currently are allowed for SAVE values but they cannot really be used because it is not clear what they are supposed to mean in this context. Michael Deckers.