I am using Perl6 (Rakudo) and am writing a simple regex. It correctly parses, so that is not the problem. It is so slow to parse that I am using the Perl5 m:P5 prefix to be able to parse in a reasonable amount of time. They should both do the same thing.

My Perl6 code is: /^^ (<[#.]>) [\" ([ <-[\\ \"]> | . <-[\"]> | <-[\\]> . ] +) \"   |   (<-[\ ]> +)]/
My Perl5 code is: m:P5/^([#.])(?:\"((?:[^\\\"]|.[^\"]|[\\].)+)\"|([^ ]+))/

They match the same thing (any thing inside quotes including escaped quotes, or the first word) but the Perl5 version is very fast comparatively.

I am running Perl6 version 2015.03 build on MoarVM version 2015.03. And just so you all know, I put a print statement before the first test, between the tests, then after them and it was definitely much (as in seconds) slower to use Perl6. Why is this?

Edit: I just changed my code to remove the  <-[\\ \"]> | and the [^\\\"]| and it pretty much removed the difference. That's really weird.

In reply to Perl6 Regex extremely slow by czipperz

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