There are probably already packages that do this — particularly if you're really only interested in math expressions. However, if you wish to write your own reasonably safe math parser/grammar, a good place to start might be: Parse::RecDescent.

Another direction you could go is the Safe module. I doubt I'd execute code from some random third party on my computers, but if I did, I'd use Safe and a chroot and probably various other things — and still lose sleep over it.

-Paul

In reply to Re: eval question by jettero
in thread eval question by Anonymous Monk

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