Doesn't work. (?!) just makes it take the second alternative. People have proposed a FAIL HERE mechanism, but there isn't one now.

The alternate way (much worse than hv's IMO) that you sometimes see is (IIRC) /^(.(?!$regex))*\z/s

In reply to Re^2: negative regex without !~ by ysth
in thread negative regex without !~ by mbr

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