http://www.perlmonks.org?node_id=88314


in reply to Re: Re: using a hash to do substitution?
in thread using a hash to do substitution?

On the other hand, an alternating regex can use the /o modifier, while your version can't. Regex compilation is a costly operation, so alternation should be much faster under /o.
   MeowChow                                   
               s aamecha.s a..a\u$&owag.print