DST rules are just insane. I'm responsible for some code where I just drew the line and 40 some odd people in one of the Antarctic stations are just going to have to live with wrong time part of the year if they ever run my code. I'm not adding another code path and test case just because these people wanted their own special concept of time. I don't remember the pattern, but I think it was maybe a daylight savings time and then an extra one stacked in the middle.

We have endless problems with DST as well. I can't wait for the EU directive that abolishes it. Russia dropped it years ago. We'll still have to support past times and other timezones though.

I wonder how long time it will take to forget DST if it is abolished. Will that messy spaghetti code be ripped out and never seen again.

Most standard libraries still have support for the Julian calendar. That stuff is never going away.

Julian calendar is still used by the US Navy. Every supply department office you go into has a conversion table up on the wall.

I doubt it's "most". Python, Javascript, and C++ don't seem to. The only ones I found that do seem to are C# and Java.

I just got a ruby gem from someone who actually made tables on the stuff. I made a script that cut out far past and future times to lower loading time from 10m to 30s and figured I could upgrade the gem to leverage an expert’s research as timezones changed (e.g. India changing zones)

Yeah I always feel like a jerk when people open tickets in the summer saying “Please do this at #:## EST” and I have to reply “thanks for providing a time but it’s currently EDT in NYC. Is that what you meant?”

No reason to be snarky with people. They mean whatever time it currently is or will be.

Are you sure though?

If they copied that date from some automated system it might as well be any of these.

Humans usually say “New York time”.

In my experience, humans never say "New York time", or "San Francisco time", or anything like that, they say "EST" and "PST" regardless of whether daylight saving's is on.

I'm guilty of this too, since I can never remember which part of the year constitutes "on" and which is "off", only where the boundaries are. If I stop and think I can usually remember "spring ahead is turning it on", but never off the top of my head.

That's only slightly worse than how I feel when people say that something's happening in the summer when it's actually winter where I live.

I hear you. It almost always is what people meant but most of us (myself included) rarely think about the distinction.

I've just gotten to saying ET (or equivalent) all year-round .

That’s the battle I fight: persuading people that saying “Eastern” is accurate and sufficiently precise. Precise and inaccurate is a bad combination.

That becomes fairly obvious when you consider Arizona doesn't observe DST, but Utah is the same longitude (lies directly north) and does observe DST.

Yep. And there also small regions that observe daylights savings WITHIN regions that don’t observe daylight savings WITHIn regions that do observe it. For example, in Indiana it is on a per county basis[1].

1. https://www.timeanddate.com/time/us/indiana-time.html

Speaking of within, I fibbed slightly about Arizona.

https://en.wikipedia.org/wiki/Time_in_Arizona

The Navajo Nation is within Arizona's boundaries, and it does observe DST. And the Hopi Reservation is within the Navajo Nation, and it does not observe DST.

And since Arizona is surrounded by California, Nevada, Utah, New Mexico, and Mexico, all of which do observe DST, that means you have an island of no-DST (Hopi) inside an island of DST (Navajo) inside an island of no-DST (Arizona) inside an area of DST (adjoining US states plus Mexico).

How did we screw up time zones so much?

We invented and then implemented time zones and then invented and then implemented daylight savings time; arbitrarily and with arbitrary laws and treaties.

There are days where I think I should go back to a mechanical watch and adjust the time each day at high noon. It won’t agree with anyone else’s time most of the time, but at least it will be correct.

But won't it be wrong as soon as you start travelling east or west, though?

Well that's almost enough to make one think daylight saving time is a bunch of cracked-up nonsense!

Somewhere I have an old book which includes time zone maps for Indiana in the 50s and 60s. Every single year there were changes.

There's also half hour timezones, found at least in India, and I think a couple quarter hour zones.

And that it's possible for two places to be more than 24 hours apart.