[rieTohgh6]

I am more surprised it is about numbers. I found it more important to take care when dealing with date ranges in databases. And SQL "BETWEEN" lures you into using [from, to], which is great way to shoot yourself in foot. So just my 2 cents:

- what are you going to do when you need to split [a,b] into multiple parts, for performance reasons? [a,c], (c,b] ? Can your codebase handle different interval types? Having [a,b) everywhere is simpler

- stuff like 23:59:59.999999999 is code smell, well until database rounds it up, to next day, then it turns into bug

[bouke]

A system I work on chose to use [closed, closed] intervals for date time intervals, where multiple intervals should be adjacent, but not overlapping. So the intervals look like 2022-11-22T00:00:00.000Z - 2022-11-22T23:59:59.999Z. Of course the codebase is sprinkled with +/- 1ms, and off-by-one issues causing date times to match _no_ interval. [closed, open) would've been so much easier to work with and reason about.