Meno Hochschild said:
@Paul Eggert When I elaborated my workaround for v2018b (which works fine now) I have made at least the assumption that a rule set consisting of rule lines having the same name will not contain a mixture of both negative and positive dst offsets. Otherwise my approach will probably be broken.
In that case your approach is broken. While I'm not aware of anywhere that has shifts both backwards and forwards from "standard time", I have no faith that politicians won't do it. For example, imagine an Islamic country decides to move forwards an hour to be in line with a major trading neighbour. So their standard time is UTC+3 and their summer time is UTC+4. But for Ramadan they still need to be close to local solar time, so that's UTC+2. Yes, this is a hypothetical, but it's not completely implausible. -- Clive D.W. Feather | If you lie to the compiler, Email: clive@davros.org | it will get its revenge. Web: http://www.davros.org | - Henry Spencer Mobile: +44 7973 377646