Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Australia/Lord_Howe is the weirdest timezone

ssoready.com

Post reply on HN
Print view View original

101–110 of 466 posts

Re: Australia/Lord_Howe is the weirdest timezone

#101

Post by NeoTar »

dfc wrote: post #97

Does anyone understand what was meant by "This is because almost every standard (except ISO8601, whatever) is just a file, and you can read it." Initially I thought it was because the PDF of ISO-8601 is not a file commonly distributed with operating system. But that's not unique to ISO8601, you won't find IEEE 1588-2019 or NMEA 0183 v4.11 on your computer either. For ~20$ I think I can buy a PDF of the standard from…

Possibly joking about the .iso file-type for optical disc images?

Or maybe that 'most' ISO standards that are encountered by engineers are defining file-types.

I'm also a big fan of ISO-3166 though !

Re: Australia/Lord_Howe is the weirdest timezone

#102

Post by jdietrich »

squiggleblaz wrote: post #19

I kind of thing a half hour daylight savings difference instead of an hour is a pretty low bar for the weirdest timezone. Almost any of the others are weirder: Antarctica/Troll definitely sounds weirder. The Moroccan and Gazan timezones that can't be expressed by the system as it was written because at least that means that they have some different kind of a rule, even if lunar time is well known. Same with the ones…

Leap seconds are generally trivia, but they become absolutely crucial in applications where multiple parties must be in exact agreement about chronology - the obvious example being financial transactions. A lot of markets were closed for the leap second and many banks still suspend all transactions during any change of local time to mitigate the risk of error.

Even in applications where we don't particularly care, there have been a surprisingly large number of leap second-related bugs. CGPM have decided to abolish the leap second for good reason.

https://en.wikipedia.org/wiki/Leap_second#Other_reported_sof...

Re: Australia/Lord_Howe is the weirdest timezone

#103

Post by fouronnes3 »

dalmo3 wrote: post #61
fouronnes3 wrote: post #24

What I like about the tz database is that's it's technically a diff of a diff. It stores the difference across history, of the difference of each timezone with UTC. Right? So it's a diff^2. But! The tz database gets updates! So those commits are diffs of diffs of diffs, or diff^3. Can we go further? You bet! It has a changelog, and that changelog is stored in git, so commits to the tz changelog are diff^4: they are c…

You forgot that UTC (or timekeeping in general) itself is a diff.

Oh that's a great point! We have achieved diff^5 at last!

Now that I think of it, we could even stretch it one more level. In practice UTC is "realized" as a "best of" diff to atomic clocks in labs around the world, which are themselves diff against a fixed time point, as you pointed out. So that realization technically changes when the official UTC bulletin[1] is published by BIPM. So diff^6!

[1] https://www.bipm.org/en/time-metrology

Re: Australia/Lord_Howe is the weirdest timezone

#104

Post by FateOfNations »

yokoprime wrote: post #86
entuno wrote: post #80

The time zone in Palestine is a bit weird as well: https://en.wikipedia.org/wiki/Time_in_the_State_of_Palestine They have DST, but it's not on fixed dates, the government just announces each year when it's going to start and end. Sometimes with less that a week's notice, which must cause all kinds of interesting problems for people.

Without getting deep into politics I don't understand why they would prioritize spending effort on DST at all, seems like there are plenty of other concerns.

Most of the population there is interested in those dates for non-DST-related reasons. They will want to know when Ramadan begins and ends, regardless of whether it's used to determine DST.

Re: Australia/Lord_Howe is the weirdest timezone

#105

Post by Kwpolska »

> Yeah, this stuff is weird, but only finitely so, because ultimately a computer’s gotta implement them

Historic data can be recorded. Rules like "last Sunday in October" or "first day of Ramadan" can be implemented and handled automatically (even if the current Unix implementations don’t do non-Gregorian calendars out-of-the-box). But there can be time zones whose DST rules are "if the groundhog sees its shadow, we start DST two weeks later, otherwise, there is no DST this year". Some countries actually implement this, except the groundhog is replaced by your friendly local regime.

Re: Australia/Lord_Howe is the weirdest timezone

#106

Post by [deleted] »

entuno wrote: post #80

The time zone in Palestine is a bit weird as well: https://en.wikipedia.org/wiki/Time_in_the_State_of_Palestine They have DST, but it's not on fixed dates, the government just announces each year when it's going to start and end. Sometimes with less that a week's notice, which must cause all kinds of interesting problems for people.

[deleted]

Re: Australia/Lord_Howe is the weirdest timezone

#108

Post by FateOfNations »

imrejonk wrote: post #39

I find it slightly ironic that a blog that’s educating (and entertaining) us on time and timezones does not itself mention when its blogposts were published, at least on mobile. This one appears to have been published in the summer of 2024.

For a while (currently?) there was SEO "wisdom" going around about not putting dates on content so that search engines would treat the content as "evergreen" rather than "stale".

Re: Australia/Lord_Howe is the weirdest timezone

#109

Post by tuoret »

rozenmd wrote: post #51
imrejonk wrote: post #39

I find it slightly ironic that a blog that’s educating (and entertaining) us on time and timezones does not itself mention when its blogposts were published, at least on mobile. This one appears to have been published in the summer of 2024.

Seems like pretty timeless content to me.

There's a couple of things that made me think the article was way older than it actually is (and made me mildly irritated that it doesn't include the publication date).

First off, the author starts off by talking about GMT and goes on to educate the reader how UTC is actually the current standard. Maybe it's just me but I thought this would be common knowledge by now, while the author frames this as some sort of a revelation.

Then there's the jab about The IERS breaking Wikipedia's css which just doesn't seem to happen on the two devices I opened it on, so I assumed that was the case prior to Wikipedia's redesign.

Minor things for sure, and the content itself is pretty timeless (heh).

Re: Australia/Lord_Howe is the weirdest timezone

#110

Post by macspoofing »

grotorea wrote: post #98
yokoprime wrote: post #86

Earlier quoted context omitted.

Without getting deep into politics I don't understand why they would prioritize spending effort on DST at all, seems like there are plenty of other concerns.

I don't see why announcing DST would be a big effort. And it saves on electricity costs.

Announcing is not a big effort. Having millions of people, and thousands of companies (in the territory and outside the territory) adjusting to the announcement is a big effort. If you're going to have DST, you want it to be stable and predictable so that people can plan for it.
Post reply on HN