• Incidentally, Perl uses a traditional NFA engine for regex matching. If it used the POSIX-NFA engine or a DFA engine, your regex would work as you expect because those engines try to find the longest match that satisfies the regex.

Weeeeell, kinda. A DFA engine in general can't do backreferences, so he wouldn't have been able to test the $1 thing to begin with...

You're right about the POSIX NFA, though. Of course, no one would use Perl RExen if they were POSIX NFAs, as they'd be too slow. But you knew that :-).

-dlc

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