$oldpat = '-([0-9]+)-';
$newpat = '"_$1_"'; # note double quotes in single quotes

$newname = $oldname;
$newname =~ s/$oldpat/$newpat/ee; # note double ee
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Works. But you'd better be very careful about what replacement strings are entered!

It will eval '"_$1_"' to mean "_$1_" and then replace the match with what that expression (not string) returns.

Anyway, contrary to what mattriff said, just putting the $newpat in double quotes will interpolate $1 before the match is run, so that won't work.

-- 
Joost       downtime n. The period during which a system
            is error-free and immune from user input.
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