this post was submitted on 31 Oct 2024
334 points (97.2% liked)

Programmer Humor

32591 readers
947 users here now

Post funny things about programming here! (Or just rant about your favourite programming language.)

Rules:

founded 5 years ago
MODERATORS
 

^.?$|^(..+?)\1+$

Matches strings of any character repeated a non-prime number of times

https://www.youtube.com/watch?v=5vbk0TwkokM

you are viewing a single comment's thread
view the rest of the comments
[–] MummifiedClient5000@feddit.dk 4 points 1 month ago (1 children)

Only the part after the pipe character. The pipe character works as an "or" operator. RegalPotoo is right.

[–] NateNate60@lemmy.world 3 points 1 month ago (1 children)

They said—

A line with exactly 0 or 1 characters, or a line with a sequence of 1 or 3 or more characters, repeated at least twice

Note—

...or a line with a sequence of 1 or 3 or more characters, repeated at least twice

It should be—

...or a line with a sequence of 2 or more characters, repeated at least twice

The regex in the post will match "abab". Their original description (line 2 of this comment) will not match "abab".

[–] MummifiedClient5000@feddit.dk 4 points 1 month ago

I agree, you're right about the part after the pipe and RegalPotoo's explanation was not entirely correct.