Sorry, your benchmark is too complicated, I can't easily tell how often the inner loop is executed.

If it's just several times then your results may be explained by the overhead to initialize qr.

Another guess is to try $s =~ /$re/; instead of $s =~ $re; (which is admittedly counterintuitive)

Can't test, sorry.

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Wikisyntax for the Monastery

In reply to Re: Performance penalty of using qr// by LanX
in thread Performance penalty of using qr// by Athanasius

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