Comment by abustamam

Comment by abustamam 20 hours ago

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I always found it weird when systems code dates as DateTime strings. There needs to be a different primitive for Date, which is inherently timezone-less, and DateTime, which does require a timezone.

After having a bunch of problems with dealing with Dates coded as DateTime, I've begun coding dates as a Date primitive, and wrote functions for calculation between dates ensuring that timezone never creeps its way into it. If there is ever a DateTime string in a Date column in the database, it's impossible to know what the date was supposed to be unless you know you normalized it at some point on the way up.

Then I found that a lot of DatePicker libraries, despite being in "DATE" picker mode, will still append a local timezone to its value. So I had to write a sanitizer for stripping out the TZ before sending up to the server.

That said, I am pretty excited about Temporal, it'll still make other things easier.

mjevans 13 hours ago

There needs to be a difference between an Instant, an Instant at an Observed Location, and a 'Specification for constructing a date that might or might not have already passed or pass in the future'.

E.G. in a conversation "Lets open the shop at 9am every day that it isn't closed." Is a fairly simple recurrence, with some exceptions*. If timezones change the scheduled time remains evaluated again on each day.

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  • abustamam 12 hours ago

    Yeah that's a good point, and also takes into account the dreaded DST (what are this business's operating hours for example, which remains the same locally but would change in UTC)

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mexicocitinluez 4 hours ago

This has been a huge source of frustration in C#.

The BCL-provided DateTime was really confusing, especially when you just needed a Date. They eventually got around to including a DateOnly, but before that happened I switched to a library called "Noda" (or Joda in Java) and after a bit of a learning curve, it made everything a lot easier to reason about.

It has LocalDates and LocalDateTimes, as well as Instants to store UTC times. It also offers ZonedDateTimes, but I don't use those as much. I work in healthcare. And so many regulations involve strictly dates. Like, "You have 5 days to do X", not "You have 120 hours to do X", and as such, storing the time with a lot of this data can add more complexity.

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