[bell-cot]

(You forgot off-by-1 errors.)

All software has to name things, and count. Caching (including invalidation) is best understood as a liability. If you can foist it off on your CPU and OS and DB, good for you. Programming whatever you're actually trying to get done is already hard enough.

[yxhuvud]

Off by 1-errors is not part of the original quote, but is just a later addon to make it funny.

They also tend not to be very hard.

[TeMPOraL]

Except when they're part of some base assumptions in the domain or dozen of layers of abstractions below you. They are hard to prevent from happening.

[tombert]

They're not hard but I will say that when I was writing an app that was using both JavaScript and Julia, I kept getting off-by-one errors because Julia starts at 1 instead of 0.

Really the only time in my entire professional career that off-by-one errors have actually given me headaches.

[bobthepanda]

I think that is from a time when popular programming languages varied in their behavior and also when people were writing for loops with incrementation all the time.

A lot of languages have just settled on zero indexing, and many now have some variation of for/each or for/of that would eliminate a lot of potential ways to encounter this error.

[tombert]

Yeah, I mostly will do map/reduce/filter when possible, and obviously in those cases indexes don’t matter. It could start at index 12345 for all I care with that stuff.

Occasionally, though, I need to use the same index across multiple items, there’s not a trivial means in which to zip, and at that point I have to use an old school for loop. That’s when the 1-index vs 0-index bites me.

[Cthulhu_]

If you omit the off-by-1 error from the two hard things joke, you're still off by 1, right? Kind of?