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Re: [perl #133366] *COMMIT bug?

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From:
Abigail
Date:
July 13, 2018 07:56
Subject:
Re: [perl #133366] *COMMIT bug?
Message ID:
21535_1531468608_5B485B3F_21535_73_1_20180713080306.GB31649@almanda.fritz.box
On Fri, Jul 13, 2018 at 08:28:20AM +0100, ph10@hermes.cam.ac.uk wrote:
> On Thu, 12 Jul 2018, Abigail via RT wrote:
> 
> > What seems to happen is that the optimizer is too eager. It finds the 'D'
> > in both the pattern and the string, and determines that if the pattern
> > matches, it should start matching 2 characters before the 'D'. This is
> > a valid strategy if the (*COMMIT) is not present, but not in the presence
> > of it.
> 
> Aha! Optimizing does that kind of thing - PCRE has/had similar issues. 
> One of the PCRE users has been checking out all kinds of stuff and 
> comparing with Perl. There seem to be some odd anomalies in the handling
> of captures in negative assertions and in the handling of (*VERB)s in
> subroutine calls in Perl. Would it be helpful if I reported these as
> independent issues?


I think it would.


Abigail

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