[tz] [PROPOSED] Support SAVE suffixes, for Namibia 1994-2017

Paul Eggert eggert at cs.ucla.edu
Mon Apr 9 02:17:15 UTC 2018

Michael Deckers via tz wrote:

>     Considering that this proposal makes the setting of the dst bit
>     an issue that is independent from the circumstance of whether
>     the value of a SAVE entry is zero or not,  is it not
>     desirable to completely  avoid the use of negative SAVE values
>     to express the dst bit setting, so as to make it easier for
>     parsers of zic source files to follow the changes
>     in the "bleeding edge" format?

It's more the other way around, I would think. zic has supported negative SAVE 
values for decades and most other tzdata parsers have followed suit. So if a 
timekeeping practice can be specified either way, it'll be easier on the 
installed base if we use this long-established feature than if we use the 
proposed new feature.

I get the point that we'd rather keep the syntax simpler and more regular, and 
that lessening the number of syntax features helps do that. But here I think the 
compatibility win outweighs the regularity loss.

>     for systematicness, shouldn't the same suffixes and defaults
>     also be applicable to a numeric entry in the RULE column of
>     ZONE lines?

Good point, thanks. Proposed further patch attached.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-Support-s-and-d-suffixes-in-Zone-SAVE-column-too.patch
Type: text/x-patch
Size: 5370 bytes
Desc: not available
URL: <http://mm.icann.org/pipermail/tz/attachments/20180408/2ee2a132/attachment.bin>

More information about the tz mailing list