finding out about the qr//a requirement.
There's also the max_codepoint option.
Without it, even \d may return a unicode numeral!
But! that's because your \d also matches unicode numerals, which might be one of the things you need to test when validating your code works as expected for all possible inputs. People can get a false sense of security by comparing a html form input against /^\d+$/. Likewise, if you end a regex with $ instead of \Z your regex will tolerate a trailing \n, so that is one of the things this module can generate.
