So I created a 50k.txt file and ran the the function for all of the versions of perl that I have (I have one of each major version installed).

For 5.8, 5.10, 5.12, 5.14, 5.16, and 5.18, it took around 11s to run. Starting at 5.20 and on, it took 30s to run. I've been looking through the perldelta doc for 5.20 at the regexp related stuff, and there are several changes, but I'm not seeing one that jumps out as related to this specifically... but it's at least a place to start. The 5.20 version is definitely where the jump happened.

FWIW, I was using the last 5.20.3 release... I did not test earlier 5.20 releases, so I have not narrowed it down to the specific 5.20 release.

In reply to Re: regex gotcha moving from 5.8.8 to 5.30.0? by SBECK
in thread regex gotcha moving from 5.8.8 to 5.30.0? by mordibity

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