I know of no RE engine that does it, but the idea I outlined in this conversation would enable the above optimization, obviate most needs for loop unrolling, get rid of most possible performance hangs, but wouldn't actually save the whales. Gosh, darn.

OTOH doing it would take some work and thought, and I am definitely not going to undertake the project any time soon.

In reply to Re (tilly) 1: Perl's regex engine causes me distress by tilly
in thread Perl's regex engine causes me distress by japhy

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