GNU bug report logs - #5373
Example in font-lock-add-keywords should use shy subgroup

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Package: emacs;

Reported by: Lennart Borgman <lennart.borgman <at> gmail.com>

Date: Wed, 13 Jan 2010 10:27:01 UTC

Severity: normal

Done: Chong Yidong <cyd <at> stupidchicken.com>

Bug is archived. No further changes may be made.

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Report forwarded to owner <at> debbugs.gnu.org, bug-gnu-emacs <at> gnu.org:
bug#5373; Package emacs. (Wed, 13 Jan 2010 10:27:01 GMT) Full text and rfc822 format available.
Acknowledgement sent to Lennart Borgman <lennart.borgman <at> gmail.com>:
New bug report received and forwarded. Copy sent to bug-gnu-emacs <at> gnu.org. (Wed, 13 Jan 2010 10:27:01 GMT) Full text and rfc822 format available.

Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Lennart Borgman <lennart.borgman <at> gmail.com>
To: emacs-pretest-bug <at> gnu.org
Subject: Example in font-lock-add-keywords should use shy subgroup
Date: Wed, 13 Jan 2010 11:26:03 +0100

Should not the second regexp in

 (font-lock-add-keywords 'c-mode
  '(("\\<\\(FIXME\\):" 1 font-lock-warning-face prepend)
    ("\\<\\(and\\|or\\|not\\)\\>" . font-lock-keyword-face)))

use a shy subgroup like in

 (font-lock-add-keywords 'c-mode
  '(("\\<\\(FIXME\\):" 1 font-lock-warning-face prepend)
    ("\\<\\(?:and\\|or\\|not\\)\\>" . font-lock-keyword-face)))



Same problem with the second example.
Information forwarded to owner <at> debbugs.gnu.org, bug-gnu-emacs <at> gnu.org:
bug#5373; Package emacs. (Wed, 13 Jan 2010 15:19:02 GMT) Full text and rfc822 format available.

Message #8 received at 5373 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Lennart Borgman <lennart.borgman <at> gmail.com>
Cc: 5373 <at> debbugs.gnu.org
Subject: Re: bug#5373: Example in font-lock-add-keywords should use shy
	subgroup
Date: Wed, 13 Jan 2010 10:18:08 -0500

> Should not the second regexp in

>  (font-lock-add-keywords 'c-mode
>   '(("\\<\\(FIXME\\):" 1 font-lock-warning-face prepend)
>     ("\\<\\(and\\|or\\|not\\)\\>" . font-lock-keyword-face)))

> use a shy subgroup like in

>  (font-lock-add-keywords 'c-mode
>   '(("\\<\\(FIXME\\):" 1 font-lock-warning-face prepend)
>     ("\\<\\(?:and\\|or\\|not\\)\\>" . font-lock-keyword-face)))

It could.  But the use of a normal group is harmless.


        Stefan
Information forwarded to owner <at> debbugs.gnu.org, bug-gnu-emacs <at> gnu.org:
bug#5373; Package emacs. (Wed, 13 Jan 2010 15:21:02 GMT) Full text and rfc822 format available.

Message #11 received at 5373 <at> debbugs.gnu.org (full text, mbox):

From: Lennart Borgman <lennart.borgman <at> gmail.com>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: 5373 <at> debbugs.gnu.org
Subject: Re: bug#5373: Example in font-lock-add-keywords should use shy 
	subgroup
Date: Wed, 13 Jan 2010 16:19:33 +0100

On Wed, Jan 13, 2010 at 4:18 PM, Stefan Monnier
<monnier <at> iro.umontreal.ca> wrote:
>> Should not the second regexp in
>
>>  (font-lock-add-keywords 'c-mode
>>   '(("\\<\\(FIXME\\):" 1 font-lock-warning-face prepend)
>>     ("\\<\\(and\\|or\\|not\\)\\>" . font-lock-keyword-face)))
>
>> use a shy subgroup like in
>
>>  (font-lock-add-keywords 'c-mode
>>   '(("\\<\\(FIXME\\):" 1 font-lock-warning-face prepend)
>>     ("\\<\\(?:and\\|or\\|not\\)\\>" . font-lock-keyword-face)))
>
> It could.  But the use of a normal group is harmless.


I thought it was slower?
Information forwarded to owner <at> debbugs.gnu.org, bug-gnu-emacs <at> gnu.org:
bug#5373; Package emacs. (Wed, 13 Jan 2010 16:02:02 GMT) Full text and rfc822 format available.

Message #14 received at 5373 <at> debbugs.gnu.org (full text, mbox):

From: Chong Yidong <cyd <at> stupidchicken.com>
To: Lennart Borgman <lennart.borgman <at> gmail.com>
Cc: 5373 <at> debbugs.gnu.org, Stefan Monnier <monnier <at> iro.umontreal.ca>
Subject: Re: bug#5373: Example in font-lock-add-keywords should use shy
	subgroup
Date: Wed, 13 Jan 2010 11:01:19 -0500

Lennart Borgman <lennart.borgman <at> gmail.com> writes:

>> It could.  But the use of a normal group is harmless.
>
> I thought it was slower?

No, it's not.  Maybe you're thinking about greedy matching?  Anyway, I'm
going to close this bug.
bug closed, send any further explanations to Lennart Borgman <lennart.borgman <at> gmail.com> Request was from Chong Yidong <cyd <at> stupidchicken.com> to control <at> debbugs.gnu.org. (Wed, 13 Jan 2010 16:02:03 GMT) Full text and rfc822 format available.
Information forwarded to owner <at> debbugs.gnu.org, bug-gnu-emacs <at> gnu.org:
bug#5373; Package emacs. (Wed, 13 Jan 2010 16:09:01 GMT) Full text and rfc822 format available.

Message #19 received at 5373 <at> debbugs.gnu.org (full text, mbox):

From: Lennart Borgman <lennart.borgman <at> gmail.com>
To: Chong Yidong <cyd <at> stupidchicken.com>
Cc: 5373 <at> debbugs.gnu.org, Stefan Monnier <monnier <at> iro.umontreal.ca>
Subject: Re: bug#5373: Example in font-lock-add-keywords should use shy 
	subgroup
Date: Wed, 13 Jan 2010 17:08:12 +0100

On Wed, Jan 13, 2010 at 5:01 PM, Chong Yidong <cyd <at> stupidchicken.com> wrote:
> Lennart Borgman <lennart.borgman <at> gmail.com> writes:
>
>>> It could.  But the use of a normal group is harmless.
>>
>> I thought it was slower?
>
> No, it's not.  Maybe you're thinking about greedy matching?  Anyway, I'm
> going to close this bug.


No, I was not. I just thought finding the extra match data was a bit slower.

Thanks for telling.
Information forwarded to owner <at> debbugs.gnu.org, bug-gnu-emacs <at> gnu.org:
bug#5373; Package emacs. (Wed, 13 Jan 2010 18:59:02 GMT) Full text and rfc822 format available.

Message #22 received at 5373 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Lennart Borgman <lennart.borgman <at> gmail.com>
Cc: Chong Yidong <cyd <at> stupidchicken.com>, 5373 <at> debbugs.gnu.org
Subject: Re: bug#5373: Example in font-lock-add-keywords should use shy
Date: Wed, 13 Jan 2010 13:58:50 -0500

>>>> It could.  But the use of a normal group is harmless.
>>> I thought it was slower?
>> No, it's not.  Maybe you're thinking about greedy matching?  Anyway, I'm
>> going to close this bug.
> No, I was not. I just thought finding the extra match data was a bit slower.
> Thanks for telling.

Well, it is marginally slower, but you'd be hard pressed to measure
the difference.


        Stefan
bug archived. Request was from Debbugs Internal Request <bug-gnu-emacs <at> gnu.org> to internal_control <at> debbugs.gnu.org. (Thu, 11 Feb 2010 12:24:04 GMT) Full text and rfc822 format available.
This bug report was last modified 15 years and 210 days ago.

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