You must mean re::engine::POSIX or re::engine::TRE. These modules, which give you posix regular expressions got pulled from CPAN, but you can still find them on backpan. They interpret the /x re option as the regex being an extended re.

In reply to Re^2: Any way to use "POSIX Extended Regular Expressions"? by ambrus
in thread Any way to use "POSIX Extended Regular Expressions"? by Lightknight

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