I agree with chromatic except I see a small problem with his solution. With the regular expression: 
$str =~ s/(^|[^\%](?:\%\%)*)\%\{?([_a-zA-Z]\w*)\}?/"$1".$env->{$2}/ge

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it would match on something like %{FOO or %FOO}.

How to aviod that in a single RE? I'm not quite sure... Time for me to do some digging....

In reply to Re: how can I combine these expressions? by lhoward
in thread how can I combine these expressions? by knight

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