Yes, that's right, and it explains why the posessive and atomic1 have the same performance impact.

(The parse tree that perl5.10.0 -cMre=debug -we 'm/(?:be|ea|a)++\d/' and perl5.10.0 -cMre=debug -we 'm/(?>(?:be|ea|a)+)\d/' are indeed identical).

But it doesn't explain the performance compared to the non-possessive non-atomic form.

In reply to Re^2: Performance of possessive quantifiers by moritz
in thread Performance of possessive quantifiers by moritz

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