Perl optimizes certain nested loop regex constructs similar to (...*)* in order to avoid what is pathological behavior with most regex engines. For non-pathological cases, there is a small cost to this protection.

The reason the performance significantly decreases is because that crosses the point that triggers the warning "Complex regular subexpression recursion limit (32766) exceeded" (repeatedly).

- tye        

In reply to Re: Strange behaviour of the regex engine (pathological protection) by tye
in thread Strange behaviour of the regex engine by thof

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