From: Michael Heerdegen <michael_heerdegen@web.de>
To: 58726@debbugs.gnu.org
Subject: bug#58726: 29.0.50; Bug in regexp matching with shy groups
Date: Sun, 23 Oct 2022 03:41:25 +0200 [thread overview]
Message-ID: <87y1t72u62.fsf@web.de> (raw)
Hello,
(string-match-p "\\`\\(?:ab\\)*\\'" "a") ==> 0
That's wrong, the expected result is nil. The language matched by that
regexp is {"", "ab", "abab", "ababab", ...}.
Changing to a non-shy group doesn't exploit the issue:
(string-match-p "\\`\\(ab\\)*\\'" "a") ==> nil
as expected.
I've been told (emacs-help, Bruno Barbier) that the problem exists at
least in emacs 27, emacs 28 and emacs 29.
TIA,
Michael.
next reply other threads:[~2022-10-23 1:41 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-23 1:41 Michael Heerdegen [this message]
2022-10-23 13:50 ` bug#58726: 29.0.50; Bug in regexp matching with shy groups Mattias Engdegård
2022-10-24 2:38 ` Michael Heerdegen
2022-10-24 10:55 ` Mattias Engdegård
2022-10-24 11:17 ` Michael Heerdegen
2022-10-24 11:28 ` Mattias Engdegård
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