Yes, someone actually did this and I found it running on our server
Both Monday and Sunday are used as the first day of the week with quite some regularity. It’s a completely arbitrary standard no different to "the tenth month is the one called “October”. Or dividing a day into 24 segments which are each broken into 60 smaller segments of 60 even smaller segments. You can’t say either is “wrong” per se.
Personally, I was brought up learning Sunday is the first day of the week, but at some point decided that was bullshit partly because it’s the week end. But also just from a practical standpoint when looking at a calendar, it’s useful to have the weekend days grouped together.
Funny thing, september comes from the number 7, october from 8 and november and december from 9 and 10, as the year in ancient rome was starting around march. This problem is timeless.
Huh. I knew about the problem (that’s why I used October as my example, rather than, say, February), but I was mistaken as to the cause. The way I had always heard it told, September–December don’t match their current place in the year because of the addition of July and August. But I just looked it up and it seems you’re right. Those months are merely renamings of Quintilis and Sextilis, and the numbering issue comes from moving the start of the year from March to January.
I was off by one, but Sunday is 0 in javascript
That’s nice, you can run weekend = dayOfWeek > 5 and then explain to the boss why clients are getting work texts on a sunday
