Interesting. I didn't know you couldn't eval code in a regex at run-time. Well, even without that I could still hog your CPU by passing it a regex with an exponential solving time.

As far as what you can do - don't accept a regex from an untrusted user. I don't believe there's any way to fully validate the friendliness of a regex. Maybe you could offer your users a set of pre-canned searchs "full-word search", "phrase search", "starts with", "ends with", etc. Then use the input to build the appropriate regex with \Q$term\E to quarantine the input.

-sam

In reply to Re: Re: Re: Re: How to identify invalid reg. expr.? by samtregar
in thread How to identify invalid reg. expr.? by armyk

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