Binarus wrote: >So is there any change to add an according API function to DT:TZ?
Yes, but we wouldn't want to rush it. There's more than one implementation of the API, and we want to be sure to design it correctly the first time. Perhaps it could be a ->offsets_for_local_datetime method (note plural in the name), which returns a sorted list of all the timezone offsets that are applicable to a specified local time. Normally the list would have length 1, the element being the same value returned by ->offset_for_local_datetime. Ambiguous local times (regardless of the source of ambiguity) yield more than one offset. Non-existent local times (skipped due to clocks going forward) yield an empty list without error. -zefram
