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Re: [perl #133366] *COMMIT bug?

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From:
ph10
Date:
July 13, 2018 07:28
Subject:
Re: [perl #133366] *COMMIT bug?
Message ID:
17746_1531466914_5B48549D_17746_105_1_alpine.LNX.2.20.1807130823590.9705@quercite
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?

Regards,
Philip

-- 
Philip Hazel

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