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A leap year check in three instructions

(hueffner.de)
420 points gnabgib | 3 comments | 15 May 25 21:57 UTC | HN request time: 0.031s | source
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usr1106 ◴[16 May 25 03:10 UTC] No.44001491[source]▶
Interesting. In one place the author argues: 0 is missing, but we already know...

The is no year 0, it goes 1 BC, 1 AD. So testing whether 0 is a leap year is moot.

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timewizard ◴[16 May 25 04:55 UTC] No.44001960[source]▶
ISO8601 accepts year 0. It is 1 BC in astronomical calendars. All the BC years gain a -1 offset as a result.
replies(1): >>44002145 #
usr1106 ◴[16 May 25 05:37 UTC] No.44002145[source]▶
Interesting, how standards just ignore reality.

At work we had discussions what date format to use in our product. It's for trained users only (but not IT people), English UI only, but used on several continents. Our regulatory expert propsed ISO8601. I did not agree, because that is not used anywhere in daily life except by 8 millions Swedes. I voted 15-Apr-2025 is much less prone to human error. (None of us "won". Different formats in different places still...)

replies(1): >>44002622 #
1. deredede ◴[16 May 25 07:20 UTC] No.44002622[source]▶
> that is not used anywhere in daily life

Does it matter? MM-DD-YYYY is used in America and makes DD-MM-YYYY ambiguous, but as far as I know nobody uses YYYY-DD-MM, so ISO8601 should be perfectly fine, especially if users are trained. Besides, if you're not used to it, starting with the year forces you to think, which is desirable if you want to avoid human error.

replies(1): >>44005675 #
2. dahart ◴[16 May 25 14:03 UTC] No.44005675[source]▶
I couldn’t have named the standard and never read it before today, but I’ve used YYYY-MM-DD for naming my own folders & files for a couple of decades, for the simple reason that it sorts correctly in chronological order.
replies(1): >>44017020 #
3. usr1106 ◴[17 May 25 21:16 UTC] No.44017020[source]▶
You do it, I do it, probably many programmers or other systematically thinking people do it. How big share we are of the general public? Even many programs don't do it in their default naming when saving files. I find myself renaming often enough.