That's a good trick, as long as the user's input is trusted; otherwise it may cause arbitrary perl code to execute. If you filtered their input to only letters and numbers, it would be safe.

Update:ikegami points out that this is only true if use re 'eval'; is on, and perlre(1) confirms this. \Q/\E should help with the possibility of creating a really slow regex, and reduce the chances of tickling a bug in Perl's regex engion that turns out to be exploitable.


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In reply to Re^2: matching a regular expression by sgifford
in thread matching a regular expression by s_gaurav1091

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