[masklinn]

> That's because the Python regex module caches the regexes it compiles, so it only happens once. It's proper and good usage to specify the regex string inline, even in a hot path.

Last time I had a look the regex cache was pretty small (few hundred entries) and gets completely cleared when full. Might have improved since, but historically it was very simplistic.

I disagree that it’s “proper and good usage” to specify regex inline. It’s fine for many usages but that’s as far as I’d go.

[makapuf]

Even then, hashing and lookup is completely unnecessary in a hot path. Having a variable with a compiled regex is not unpythonic AFAIK