* bug#11216: 23.4; parenthesis matching breaks on certain complex expressions
@ 2012-04-11 0:18 Nathan Trapuzzano
2012-04-11 7:09 ` Andreas Schwab
2012-04-12 2:08 ` Stefan Monnier
0 siblings, 2 replies; 4+ messages in thread
From: Nathan Trapuzzano @ 2012-04-11 0:18 UTC (permalink / raw)
To: 11216
[-- Attachment #1: Type: text/plain, Size: 2944 bytes --]
Here's a complex regular expression that breaks parenthesis matching
(and yes, that's a real regular expression generated from a real perl
program).
M[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*H[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*\=[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*N[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*I[\=\/\\]?[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*N(?![\x21\x27\x2a\x2d\x2f\x3d\x41-\x5a\x5c\x61-\x7a\x7c]) (?<!S\d)(?<!\-\ [@"]\d\ [\x80-\xff])(?<!\-[\x80-\xff][\x80-\xff])(?<!\-[\x80-\xff])(?<![\x27-\x29\x2f\x3d\x41-\x5a\x7c]\*)(?<![\x27-\x29\x2f\x3d\x41-\x5a\x7c])(?:
A\)[\/\\]|\*\)[\/\\]A[\=\/\\]?)[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*E[\=\/\\]?[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*I[\=\/\\]?[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*D[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*E[\=\/\\]?(?![\x21\x27\x2a\x2d\x2f\x3d\x41-\x5a\x5c\x61-\x7a\x7c]) (?<!S\d)(?<!\-\ [@"]\d\ [\x80-\xff])(?<!\-[\x80-\xff][\x80-\xff])(?<!\-[\x80-\xff])(?<![\x27-\x29\x2f\x3d\x41-\x5a
\x7c]\*)(?<![\x27-\x29\x2f\x3d\x41-\x5a\x7c])Q[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*E[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*A[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*[\/\\]
Matching gets messed up with the open parenthesis immediately following
the first (?<!S\d). I suspect this is due to the opening double-quote
about 10 characters later.
I noticed that the behavior of show-paren-mode changes depending on the
major mode. For example, the behavior described above happens in
fundamental mode, whereas when I switch to text mode, quotation marks
are ignored. However, switching to text mode also causes paren-matching
to ignore back-slashes and thus escaped parentheses/brackets. I think
the best fix would be to enable customization of show-paren-mode so
that the user can specify which characters should be ignored when
matching parentheses.
I've also attached a file containing the regexp in question in case the long line gets broken up over mail transmission.
[-- Attachment #2: regexp.txt --]
[-- Type: text/plain, Size: 1996 bytes --]
M[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*H[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*\=[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*N[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*I[\=\/\\]?[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*N(?![\x21\x27\x2a\x2d\x2f\x3d\x41-\x5a\x5c\x61-\x7a\x7c]) (?<!S\d)(?<!\-\ [@"]\d\ [\x80-\xff])(?<!\-[\x80-\xff][\x80-\xff])(?<!\-[\x80-\xff])(?<![\x27-\x29\x2f\x3d\x41-\x5a\x7c]\*)(?<![\x27-\x29\x2f\x3d\x41-\x5a\x7c])(?:
A\)[\/\\]|\*\)[\/\\]A[\=\/\\]?)[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*E[\=\/\\]?[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*I[\=\/\\]?[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*D[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*E[\=\/\\]?(?![\x21\x27\x2a\x2d\x2f\x3d\x41-\x5a\x5c\x61-\x7a\x7c]) (?<!S\d)(?<!\-\ [@"]\d\ [\x80-\xff])(?<!\-[\x80-\xff][\x80-\xff])(?<!\-[\x80-\xff])(?<![\x27-\x29\x2f\x3d\x41-\x5a
\x7c]\*)(?<![\x27-\x29\x2f\x3d\x41-\x5a\x7c])Q[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*E[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*A[?+]?(?:-(?:[\x01-\x7f]*[\x00\x80-\xff]+))?[\x02-\x19\x22-\x27\x28-\x2e\x30-\x3c\x3e-\x40\x5b\x5d-\x7b\x7d-\xff]*[\/\\]
^ permalink raw reply [flat|nested] 4+ messages in thread
* bug#11216: 23.4; parenthesis matching breaks on certain complex expressions
2012-04-11 0:18 bug#11216: 23.4; parenthesis matching breaks on certain complex expressions Nathan Trapuzzano
@ 2012-04-11 7:09 ` Andreas Schwab
2019-11-01 20:11 ` Stefan Kangas
2012-04-12 2:08 ` Stefan Monnier
1 sibling, 1 reply; 4+ messages in thread
From: Andreas Schwab @ 2012-04-11 7:09 UTC (permalink / raw)
To: Nathan Trapuzzano; +Cc: 11216
Nathan Trapuzzano <nbtrap@nbtrap.com> writes:
> Matching gets messed up with the open parenthesis immediately following
> the first (?<!S\d). I suspect this is due to the opening double-quote
> about 10 characters later.
No, it's because < has open paren syntax, but there is no matching
close paren. This is not a bug. You need to use a suitable syntax
table that doesn't make < a paren syntax.
Andreas.
--
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5
"And now for something completely different."
^ permalink raw reply [flat|nested] 4+ messages in thread
* bug#11216: 23.4; parenthesis matching breaks on certain complex expressions
2012-04-11 7:09 ` Andreas Schwab
@ 2019-11-01 20:11 ` Stefan Kangas
0 siblings, 0 replies; 4+ messages in thread
From: Stefan Kangas @ 2019-11-01 20:11 UTC (permalink / raw)
To: Andreas Schwab; +Cc: Nathan Trapuzzano, 11216
tags 11216 + notabug
close 11216
thanks
Andreas Schwab <schwab@linux-m68k.org> writes:
> Nathan Trapuzzano <nbtrap@nbtrap.com> writes:
>
>> Matching gets messed up with the open parenthesis immediately following
>> the first (?<!S\d). I suspect this is due to the opening double-quote
>> about 10 characters later.
>
> No, it's because < has open paren syntax, but there is no matching
> close paren. This is not a bug. You need to use a suitable syntax
> table that doesn't make < a paren syntax.
With the above explanaition, I'm closing this as notabug.
Please reopen if this is incorrect.
Best regards,
Stefan Kangas
^ permalink raw reply [flat|nested] 4+ messages in thread
* bug#11216: 23.4; parenthesis matching breaks on certain complex expressions
2012-04-11 0:18 bug#11216: 23.4; parenthesis matching breaks on certain complex expressions Nathan Trapuzzano
2012-04-11 7:09 ` Andreas Schwab
@ 2012-04-12 2:08 ` Stefan Monnier
1 sibling, 0 replies; 4+ messages in thread
From: Stefan Monnier @ 2012-04-12 2:08 UTC (permalink / raw)
To: Nathan Trapuzzano; +Cc: 11216
> Here's a complex regular expression that breaks parenthesis matching
> (and yes, that's a real regular expression generated from a real perl
> program).
[...]
> I think the best fix would be to enable customization of
> show-paren-mode so that the user can specify which characters should
> be ignored when matching parentheses.
show-paren-mode is customized by the major-mode, so all you have to do
is use the right major mode. E.g. perl-mode.
Stefan
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2019-11-01 20:11 UTC | newest]
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2012-04-11 0:18 bug#11216: 23.4; parenthesis matching breaks on certain complex expressions Nathan Trapuzzano
2012-04-11 7:09 ` Andreas Schwab
2019-11-01 20:11 ` Stefan Kangas
2012-04-12 2:08 ` Stefan Monnier
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