If I have a regex: 

  my $regex = qr(/.../); # ... implies put any pattern here

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Can I compile with qr another regex $notregex that is true if and only if $regex is false?

I know I can use $regex with !~ to get this effect, but I situations where it would be more elegant to simply pass in the new regex.

Now, supposing that this is possible. Could one write a subroutine that takes one regex as input and returns the "does not match" regex as output?

In reply to Negation/Complement of a Regex by geekondemand

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