On 1/4/19 2:54 PM, Michael H Deckers via tz wrote:
Nothing disallows the "rearguard" format for Africa/Casablanca to describe exactly the same data as the "vanguard" format, including the same setting of the dst bit -- it is just a matter of additional ZONE lines in the "rearguard" format.
True, and possibly the same thing could be said for Europe/Prague and Africa/Windhoek, although not for Europe/Dublin (at least, not until the EU DST stuff gets resolved). This is because all but Ireland currently have a small number of transitions using non-rearguard rules, and each such transition can be represented by a Zone line. That being said, it'd be a bit of a pain to convert the Rule lines to corresponding Zone lines and the benefit is almost nil. So I'm somewhat more inclined to document the current situation than to change it.
the description in the NEWS file is incorrect....
Also in either case, we must state that it is the "vanguard" format that exactly describes the data we want to describe,
I attempted to do that by installing the attached patch into the development version. Thanks for mentioning the problem.