Pattern in lookbehind

Question

My question is related with lookbehinds, I want to find all the first numbers after the word \"this\", I have the following data:

188282 this is an exam

Answer 1

It depends on your implementation of regex. You'll have to do some testing for sure.

I know that some implementations don't like this:

(?<=\d{1,5}) or (?<=\w*)

But they will work fine with this:

(?<=\d{5}) or (?<=\w{1000})

In other words, no repetition or flexible lengths.