3 ms·
> If I have a timestamp for a future event, I can convert it to UTC, store it as UTC along with the time zone and be sure that I can reliably convert it back to
by leni536 11y ago
> If I have a timestamp for a future event, I can convert it to UTC, store it as UTC along with the time zone and be sure that I can reliably convert it back to the correct “wall time” in the future
This actually looks like a subtle type safety and casting problem. Not all time specifications belong to the same type.
- majewsky 11y agoI guess they refer to jurisdictions changing their time zones or DST rules every so often. Note how they're only talking about the future, because that's where policy changes typically apply.
- x1798DE 11y agoEven if there were retroactive changes for some reason, generally when storing a time in the past, you want to know the actual time it occurred, so a conversion to UTC when storing the time stamp is unambiguous. For future dates, you are often trying to represent "wall time", not a specific point in time, which is why storing as UTC is the wrong representation - it's something that maps to the information you want, but the mapping can change between storage and retrieval.