GNU bug report logs - #72311
[PATCH] Treat period as a symbol constituent in cc-mode

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

From: Vladislav Yegorov <vlad <at> yegorov.org>
To: Vladislav Yegorov <vlad <at> yegorov.org>
Cc: bug-gnu-emacs <at> gnu.org
Subject: Re: [PATCH] Treat period as a symbol constituent in cc-mode
Date: Fri, 26 Jul 2024 21:26:34 +0200

[Message part 1 (text/plain, inline)]

I am sorry, I forgot the actual patch.

[0001-Treat-period-as-a-symbol-constituent-in-cc-mode.patch (text/patch, attachment)]

Message #8 received at 72311 <at> debbugs.gnu.org (full text, mbox):

From: Jeremy Bryant <jb <at> jeremybryant.net>
To: Vladislav Yegorov <vlad <at> yegorov.org>
Cc: Alan Mackenzie <acm <at> muc.de>, 72311 <at> debbugs.gnu.org
Subject: Re: bug#72311: [PATCH] Treat period as a symbol constituent in cc-mode
Date: Fri, 26 Jul 2024 22:37:51 +0100

Vladislav Yegorov <vlad <at> yegorov.org> writes:

> I am sorry, I forgot the actual patch.
>
> [2. text/patch; 0001-Treat-period-as-a-symbol-constituent-in-cc-mode.patch]...

Alan, any thoughts?

Message #11 received at 72311 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: Alan Mackenzie <acm <at> muc.de>, Vladislav Yegorov <vlad <at> yegorov.org>
Cc: 72311 <at> debbugs.gnu.org
Subject: Re: bug#72311: [PATCH] Treat period as a symbol constituent in cc-mode
Date: Sat, 27 Jul 2024 08:55:23 +0300

> Cc: 72311 <at> debbugs.gnu.org
> From: Vladislav Yegorov <vlad <at> yegorov.org>
> Date: Fri, 26 Jul 2024 21:26:34 +0200
> 
> Subject: [PATCH] Treat period as a symbol constituent in cc-mode
> 
> * lisp/progmodes/cc-langs.el: Classify period as a symbol constituent,
> so decimal points for example don't divide the number into two symbols.

What about stuff like 'foo.bar', where 'foo' is a struct and 'bar' is
its member? won't this change make them a single symbol?

Message #14 received at 72311 <at> debbugs.gnu.org (full text, mbox):

From: Alan Mackenzie <acm <at> muc.de>
To: Vladislav Yegorov <vlad <at> yegorov.org>
Cc: acm <at> muc.de, Eli Zaretskii <eliz <at> gnu.org>,
 Jeremy Bryant <jb <at> jeremybryant.net>, 72311 <at> debbugs.gnu.org
Subject: Re: bug#72311: [PATCH] Treat period as a symbol constituent in cc-mode
Date: Sat, 27 Jul 2024 11:26:49 +0000

Hello, Vladislav and Eli.

On Sat, Jul 27, 2024 at 11:22:11 +0200, Vladislav Yegorov wrote:

> > What about stuff like 'foo.bar', where 'foo' is a struct and 'bar'
> > is its member? won't this change make them a single symbol?

That was my first reaction, too.

> You are right, kind of forgot about that.  I think in that case a
> simple syntax table modification like my patch provides won't do the
> trick.

> My motivation for this patch was to able to use C-M-f (forward-sexp)
> to skip over decimal numbers.  What are your thoughts on defining a
> forward-sexp-function that will use a alternate syntax table in
> certain contexts? maybe a bit too hacky?

It would be possible to put a syntax-table text property on a '.' when
it is followed directly by a decimal digit, with no space between.
Maybe we could also check that there's a valid number character before
the . (space, BOL, 0-9, -, ...?), but that might be over engineering.

My next thought is, for consistency, how would we handle something like
1.381E-23?  For consistency, C-M-f ought to move forward over that
number in its entirety.  That would need some more rigorous analysis of
every piece of text, probably by a regexp, and putting syntax-table
properties on both the '.' and the '-'.  This would slow CC Mode down,
even if not by a lot.

So, it could be done, yes.  Is it worth doing, though?  I've got very
little experience of hacking files with lots of floating point constants
in them, so it's difficult for me to judge just how annoying it is for
C-M-f and C-M-b only to move over part of a number.

-- 
Alan Mackenzie (Nuremberg, Germany).

Message #17 received at 72311 <at> debbugs.gnu.org (full text, mbox):

From: Vladislav Yegorov <vlad <at> yegorov.org>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: Alan Mackenzie <acm <at> muc.de>, 72311 <at> debbugs.gnu.org
Subject: Re: bug#72311: [PATCH] Treat period as a symbol constituent in cc-mode
Date: Sat, 27 Jul 2024 11:22:11 +0200

> What about stuff like 'foo.bar', where 'foo' is a struct and 'bar' is
> its member? won't this change make them a single symbol?

You are right, kind of forgot about that.  I think in that case a simple
syntax table modification like my patch provides won't do the trick.

My motivation for this patch was to able to use C-M-f (forward-sexp) to
skip over decimal numbers.  What are your thoughts on defining a
forward-sexp-function that will use a alternate syntax table in certain
contexts? maybe a bit too hacky?

Message #20 received at 72311 <at> debbugs.gnu.org (full text, mbox):

From: Dmitry Gutov <dmitry <at> gutov.dev>
To: Alan Mackenzie <acm <at> muc.de>, Vladislav Yegorov <vlad <at> yegorov.org>
Cc: Eli Zaretskii <eliz <at> gnu.org>, Jeremy Bryant <jb <at> jeremybryant.net>,
 72311 <at> debbugs.gnu.org
Subject: Re: bug#72311: [PATCH] Treat period as a symbol constituent in cc-mode
Date: Mon, 29 Jul 2024 02:59:44 +0300

On 27/07/2024 14:26, Alan Mackenzie wrote:
> It would be possible to put a syntax-table text property on a '.' when
> it is followed directly by a decimal digit, with no space between.
> Maybe we could also check that there's a valid number character before
> the . (space, BOL, 0-9, -, ...?), but that might be over engineering.

That sounds like the better choice indeed, but given the increase in 
complexity maybe the minor improvement in behavior is not really worth 
the effort.

Message #29 received at 72311-done <at> debbugs.gnu.org (full text, mbox):

From: Stefan Kangas <stefankangas <at> gmail.com>
To: Dmitry Gutov <dmitry <at> gutov.dev>
Cc: Alan Mackenzie <acm <at> muc.de>, Eli Zaretskii <eliz <at> gnu.org>,
 Vladislav Yegorov <vlad <at> yegorov.org>, Jeremy Bryant <jb <at> jeremybryant.net>,
 72311-done <at> debbugs.gnu.org
Subject: Re: bug#72311: [PATCH] Treat period as a symbol constituent in cc-mode
Date: Sun, 23 Feb 2025 00:49:49 +0000

Dmitry Gutov <dmitry <at> gutov.dev> writes:

> On 27/07/2024 14:26, Alan Mackenzie wrote:
>> It would be possible to put a syntax-table text property on a '.' when
>> it is followed directly by a decimal digit, with no space between.
>> Maybe we could also check that there's a valid number character before
>> the . (space, BOL, 0-9, -, ...?), but that might be over engineering.
>
> That sounds like the better choice indeed, but given the increase in complexity
> maybe the minor improvement in behavior is not really worth the effort.

It sounds like this is not a change that we want to make, so I'm closing
this now.

Nevertheless, thanks for the patch, Vladislav.

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