I'd change this subtly (unless you only care to match whole words only) to: 
$regex = join("|", map(quotemeta, 
         sort { length $b <=> length $a } keys %hash));
s/($regex)/$hash{$1}/eg;

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That is, the longer keys will appear first in the alternatives list and thus they will be matched first.

Dr. Michael K. Neylon - mneylon-pm@masemware.com || "You've left the lens cap of your mind on again, Pinky" - The Brain

In reply to Re: Re: using a hash to do substitution? by Masem
in thread using a hash to do substitution? by mr.dunstan

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