[pcre-dev] [Bug 547] full regular expression support inside …

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Author: admin
Date:  
To: pcre-dev
Subject: [pcre-dev] [Bug 547] full regular expression support inside lookbehind
https://bugs.exim.org/show_bug.cgi?id=547

--- Comment #6 from Ouims <c_moi_l_master@???> ---
Yes, just some feedbacks...

I think that modern regex engine, which pcre2 is, left the 'efficiency' as well
as the 'regular' boat a long time ago.

Many, many, many typical regex pattern are nowadays written by using lookaround
and others more complex structures instead of normal alternatives and groups
and character classes. Almost everytime, this is resulting in the same result
but being achieved slower. Of course it can be made to be as good as what basic
ERE can do, but it's often not the case that the adjustement are made.

And there's no claim from regex engines supporting variable width lookbehind
that they are doing so efficiently.

I don't think that arguing it's not going to be efficient is a good reason to
not do it, I would find a reason such as perl not supporting it way better.

I guess I should convince perl people to do it hehe.

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