I am looking for a safe way to execute untrusted user regular expressions. If I have to, I'll XS up some gnu or pcre regular support into my application...

But I'm hoping there's a better way.

I briefly considered Safe.pm and running regulars on the regulars to remove things like (?{ system "rm -rvf /" }), but I decided that really wasn't reliable enough since perl gives you so many choices to execute code in your regexps.

Is there a way to do this without XS?

UPDATE: This conversation went a totally different direction than I was really thinking it would. I'm totaly fascinated by the C-stack limits of the pre 5.8.3 regexps. wow, you learn something every day.

UPDATE #2: Well after the fact, I did end up using XS to bring glibc/gnu regex into perl: POSIX::Regex.

In reply to safe untrusted regexp by jettero

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