Like Randall said, this is very likely impossible in perl (though if you succeed in writing an XS module that accomplishes this please put it on CPAN (-: )

I think the best option here is to write out a perl-module that sets up your regexes and then require it.

maybe something like:

print REGEX_MODULE_HANDLE "$REGEX{$re_name} = qr/$re_string/;";
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This will likely run a bit slower, but your development time will be a LOT shorter :-)

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