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Insane complexity of calendrically correct date and time operations

yourcalendricalfallacyis.com

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Re: Insane complexity of calendrically correct date and time operations

#11
Imagine we did not have names for months and days. Would you call the tenth month October or December? It does not make sense. Then, the other months at the start of the calendar, would you name them after phases of a military campaign of preparation for war, conquering, looting and pillaging? Would that be deemed politically correct?

On the weekday names we are not doing any better. Tuesday - named after the god of war? Doesn't make sense to me.

As for the lengths of the months, imagine if you were trying to make the case for the different lengths of months and you were trying to get buy in from your friends in accounts. Surely they would want equal amounts of days in each quarter? Imagine trying to persuade them that different lengths were better, what plausible possible reason could there be?

We learn the names of days and months by rote at a very young age. We get encultured into accepting the status quo and never questioning little details - nobody asks at school why 'Dec'-ember is month twelve.

Re: Insane complexity of calendrically correct date and time operations

#12
The leap second has a history of breaking computers. Pretty much every Linux server running Java broke in 2012, for example. 2009 saw a bunch of Linux kernels crashing in logging code. 2016 was mostly better except for Cloudflare: their systems had an assumption time never runs backwards. https://blog.cloudflare.com/how-and-why-the-leap-second-affe...

Re: Insane complexity of calendrically correct date and time operations

#13
post #7

Many of these make the weird assumption that you want to support multiple calendars. For better or worse, this is rarely the case.

I think that's a bit naive.

Properly supporting calendrical calculations serves two major purposes:

1. Serve the billions of people who don't use the Gregorian calendar or who live in areas that don't match your idea of time zones.

2. Functions as a human form of "platform independence". Properly handling dates/times quickly exposes places you've made silly assumptions or accidentally broken things. This protects you from actual bugs and ensures you avoid whatever the future version of the Y2K problem is. Such bugs are always easier to fix when you have a smaller database and fewer users.*

* In general bugs and breaking changes _never_ get easier. Every day you delay increases the pain imposed on future you and users. Obviously there is a balance - a startup needs to worry about getting to "default alive" first and foremost - but don't delay too long and where it doesn't impose an inordinate cost do it right the first time.

Re: Insane complexity of calendrically correct date and time operations

#14

The leap second has a history of breaking computers. Pretty much every Linux server running Java broke in 2012, for example. 2009 saw a bunch of Linux kernels crashing in logging code. 2016 was mostly better except for Cloudflare: their systems had an assumption time never runs backwards. https://blog.cloudflare.com/how-and-why-the-leap-second-affe...

This is why some Google and AWS smear the leap second.

https://developers.google.com/time/smear

https://aws.amazon.com/blogs/aws/look-before-you-leap-the-co...

Re: Insane complexity of calendrically correct date and time operations

#16
post #7

Many of these make the weird assumption that you want to support multiple calendars. For better or worse, this is rarely the case.

I think that's a bit naive. Properly supporting calendrical calculations serves two major purposes: 1. Serve the billions of people who don't use the Gregorian calendar or who live in areas that don't match your idea of time zones. 2. Functions as a human form of "platform independence". Properly handling dates/times quickly exposes places you've made silly assumptions or accidentally broken things. This protects you…

I didn't say you would Never want to support multiple calendars, but like I said. For better or worse, most software written will not.

Re: Insane complexity of calendrically correct date and time operations

#19

The leap second has a history of breaking computers. Pretty much every Linux server running Java broke in 2012, for example. 2009 saw a bunch of Linux kernels crashing in logging code. 2016 was mostly better except for Cloudflare: their systems had an assumption time never runs backwards. https://blog.cloudflare.com/how-and-why-the-leap-second-affe...

Not wanting to be a complete BSD bigot, I can't actually remember if this broke in the {Free,Net,Open}BSD world as badly. The 2015 docs for FreeBSD don't help (oh, for a time machine) but go to "you can test what we do" which is good.

https://www.freebsd.org/doc/en_US.ISO8859-1/articles/leap-se...

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