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From: Nikolai Weibull <now@bitwi.se>
To: Stefan Monnier <monnier@iro.umontreal.ca>
Cc: emacs-devel@gnu.org, Colin Fraizer <emacs-devel@cfraizer.com>,
	t.matsuyama.pub@gmail.com
Subject: Re: Patch for lookaround assertion in regexp
Date: Tue, 24 Jan 2012 09:41:11 +0100	[thread overview]
Message-ID: <CADdV=Mub5CeNRSD+aNvHYERCm-zY3S00LydjfmMNq55g=GdpVg@mail.gmail.com> (raw)
In-Reply-To: <jwv7h0iike3.fsf-monnier+emacs@gnu.org>

On Mon, Jan 23, 2012 at 15:11, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
>> In 2009, Tomohiro Matsuyama sent a message to this list with a patch
>> to add lookahead/lookbehind assertions to Emacs regular expressions
>> (regexps).  Is there any plan to incorporate this useful feature into
>> an official release?

> I'd like to replace the current regexp engine with one that does not
> suffer from exponential blowup (i.e. using "Thompson's NFA").

> OTOH, noone has submitted code to replace the current regexp engine, and
> I don't forsee I'll have the time to write it myself, so maybe I should
> just give up on this plan.

As an alternative to PCRE, which, as has already been pointed out,
doesn’t match any of these requirements, how about RE2?

http://code.google.com/p/re2/

It’s written in C++, which is a minus, but it should be simple enough
to extend it with \c and \s.



  parent reply	other threads:[~2012-01-24  8:41 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-23 11:17 Patch for lookaround assertion in regexp Colin Fraizer
2012-01-23 14:11 ` Stefan Monnier
2012-01-23 14:44   ` Tom
2012-01-23 14:50     ` Andreas Schwab
2012-01-23 15:19       ` Tom
2012-01-23 16:14         ` Andreas Schwab
2012-01-23 17:11           ` Stefan Monnier
2012-01-23 18:45             ` Štěpán Němec
2012-01-30  0:31               ` Juri Linkov
2012-01-23 15:31     ` Stefan Monnier
2012-01-24  8:41   ` Nikolai Weibull [this message]
2012-01-24 14:40     ` Stefan Monnier
2012-01-24 15:09       ` Nikolai Weibull
2012-01-24 17:34         ` Stefan Monnier
2012-01-24 23:27     ` David De La Harpe Golden
2012-01-25  6:07       ` Nikolai Weibull
2012-02-14 17:53   ` Daniel Colascione
2012-02-14 18:36     ` Stefan Monnier
2012-02-20 16:19     ` Dimitri Fontaine
2012-09-26  6:55 ` Tomohiro Matsuyama
  -- strict thread matches above, loose matches on Subject: below --
2009-06-03 23:04 Tomohiro MATSUYAMA
2009-06-04  4:47 ` Miles Bader
2009-06-04  8:27   ` Deniz Dogan

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