jonskeet

I think you've misunderstood what's changing here. It's not a matter of time zones not knowing that rules vary across time. It's a matter of knowing that "the rules for 2022" vary over time as well - in that the rules I might predict for 2022 may well not be the case now.

"Time zone history" (in every platform I've seen) does not mean "knowing what the rules for 2022 were in 2019". They mean "getting things right according to all the currently-known rules, across all of history". That's very different.

I've mentioned a few times to MS folks that I'd be very happy for the mscorlib team to make Noda Time redundant. They haven't bitten yet though.

Well, my C# book (C# in Depth) has been well received. I'd like to think my date/time library for .NET (Noda Time) is mostly well-written.

But no, nothing that I'd expect to put me in the top 15 (or top 1500) programmers in the world.

Most high calibre devs would be still wrapping their head around the problem after 15 minutes. reply

Most high calibre devs haven't stumbled into doing a lot of date/time work. That wasn't some clever decision on my part - it was working on the calendar part of Google Mobile Sync. Date and time is a rabbit hole that I just went deep on. A bit of luck rather than spectacular wide knowledge, I'm afraid.

I love that question and answer too, although I doubt that it's genuinely helped many people. Time zone and calendar stuff has a lot of amusing trivia. My favourite involves the 30th of February, which only occurred in 1712, and only in Sweden.

The biggest issue with idolizing people this much in my opinion is that it puts a huge divide between you and that idol.

If it's any help, I'd be happy to give a huge list of bugs I've caused due to inexperience and incompetence.

I'm not going to pretend I don't enjoy the micro-celebrity status SO has given me, but I'd be happy to help correct any impression that there's a huge gulf between me and any "regular" programmer. Maybe a gulf in "time spent answering questions on SO" but not some massive intellectual divide.

They're not meaningful at all. Hopefully relatively few people really think I'm one of the "top 15 living programmers" or anything like that.

I'm good enough to make a living, and good enough to help people on SO. One of the nice things about programming is that what you find interesting, I might not and vice versa - hopefully there will always be enough people who find a variety of topics interesting to hope those who have problems in those topics. But yes, considering rep as a proxy metric for programming awesomeness would be a mistake IMO.

If you want to indicate a time zone you shouldn't just use the offsets - they're ambiguous in that several different time zones can have the same offset at any point in time.

Better (IMO) to use the zoneinfo ID, e.g. "Europe/London" - along with the offset as well, in case the local time is ambiguous in that time zone due to a daylight saving transition.

I wonder if it deals with Sweden properly if you're there.

cal 2 1712

should show February 30th...

http://en.wikipedia.org/wiki/February_30#Swedish_calendar

Oh there are plenty of time zones which aren't "on the hour". But most of them either don't observe DST or are unimaginitive about it.

I was far more impressed by Nepal's proposal (later dropped, I believe) to have a 1:15 daylight saving transition:

http://www.timeanddate.com/news/time/nepal-daylight-saving-t...

I only tick in .NET.

In Java I millisecond instead.