From: Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
To: "Mattias Engdegård" <mattias.engdegard@gmail.com>
Cc: 64128@debbugs.gnu.org, eggert@cs.ucla.edu
Subject: bug#64128: regexp parser zero-width assertion bugs
Date: Sat, 17 Jun 2023 14:44:30 -0400 [thread overview]
Message-ID: <jwv4jn6orpn.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: <E8949338-37DF-41DF-A295-46510F03515C@gmail.com> ("Mattias Engdegård"'s message of "Sat, 17 Jun 2023 14:20:27 +0200")
> (and (string-match "quack,\\b*" "quack,quack,quack,quaaaack!")
> (match-data))
> => (0 18)
That's so bizarre that it feels like we really should try and preserve
it for posterity.
Not.
> These regexp patterns should be very rare in practice: they should
> always be a mistake, but it would be nice if they behaved in a way
> that makes some kind of sense.
>
> A modest improvement would be to make operators become literal after
> any zero-width assertion, so that
I think the behavior that makes most sense is to signal an error when
compiling the regexp.
Stefan
next prev parent reply other threads:[~2023-06-17 18:44 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-17 12:20 bug#64128: regexp parser zero-width assertion bugs Mattias Engdegård
2023-06-17 18:44 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors [this message]
2023-06-17 20:07 ` Mattias Engdegård
2023-06-17 22:18 ` Paul Eggert
2023-06-18 4:55 ` Eli Zaretskii
2023-06-18 20:26 ` Mattias Engdegård
2023-06-19 3:04 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-06-19 8:44 ` Mattias Engdegård
2023-06-19 12:54 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-06-19 18:34 ` Mattias Engdegård
2023-06-19 19:21 ` Paul Eggert
2023-06-19 19:52 ` Mattias Engdegård
2023-06-19 20:08 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-06-20 11:36 ` Mattias Engdegård
2023-06-21 6:08 ` Paul Eggert
2023-06-21 15:57 ` Mattias Engdegård
2023-06-19 20:40 ` Paul Eggert
2023-06-19 18:14 ` Paul Eggert
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