Re: emacs-29 dc78779c0c: Fix SVG scaling (bug#59802)

Re: emacs-29 dc78779c0c: Fix SVG scaling (bug#59802)

[Po Lu]

Eli Zaretskii <eliz@gnu.org> writes:

> +	  if (! (0 < viewbox_width) && (iwidth.unit == RSVG_UNIT_PERCENT))
> +	    viewbox_width = (viewbox_height * viewbox.width / viewbox.height)
> +	      * iwidth.length;
> +	  else if (! (0 < viewbox_height) && (iheight.unit == RSVG_UNIT_PERCENT))
> +	    viewbox_height = (viewbox_width * viewbox.height / viewbox.width)
> +	      * iheight.length;

Our style is to write:

  viewbox_width = ((viewbox_height * viewbox.width / viewbox.height)
  		   * iwidth.length);

and not:

  viewbox_width = (viewbox_height * viewbox.width / viewbox.height)
    * iwidth.length;

Thanks.

Re: emacs-29 dc78779c0c: Fix SVG scaling (bug#59802)

[Eli Zaretskii]

> From: Po Lu <luangruo@yahoo.com>
> Cc: Manuel Giraud <manuel@ledu-giraud.fr>
> Date: Sat, 17 Dec 2022 09:26:08 +0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > +	  if (! (0 < viewbox_width) && (iwidth.unit == RSVG_UNIT_PERCENT))
> > +	    viewbox_width = (viewbox_height * viewbox.width / viewbox.height)
> > +	      * iwidth.length;
> > +	  else if (! (0 < viewbox_height) && (iheight.unit == RSVG_UNIT_PERCENT))
> > +	    viewbox_height = (viewbox_width * viewbox.height / viewbox.width)
> > +	      * iheight.length;
> 
> Our style is to write:
> 
>   viewbox_width = ((viewbox_height * viewbox.width / viewbox.height)
>   		   * iwidth.length);
> 
> and not:
> 
>   viewbox_width = (viewbox_height * viewbox.width / viewbox.height)
>     * iwidth.length;

There's nothing wrong with the original style, although I agree that
using extra parentheses makes it more plausible.  There's no reason to
be so stringent in insisting on the other style.

Re: emacs-29 dc78779c0c: Fix SVG scaling (bug#59802)

[Po Lu]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Po Lu <luangruo@yahoo.com>
>> Cc: Manuel Giraud <manuel@ledu-giraud.fr>
>> Date: Sat, 17 Dec 2022 09:26:08 +0800
>> 
>> Eli Zaretskii <eliz@gnu.org> writes:
>> 
>> > +	  if (! (0 < viewbox_width) && (iwidth.unit == RSVG_UNIT_PERCENT))
>> > +	    viewbox_width = (viewbox_height * viewbox.width / viewbox.height)
>> > +	      * iwidth.length;
>> > +	  else if (! (0 < viewbox_height) && (iheight.unit == RSVG_UNIT_PERCENT))
>> > +	    viewbox_height = (viewbox_width * viewbox.height / viewbox.width)
>> > +	      * iheight.length;
>> 
>> Our style is to write:
>> 
>>   viewbox_width = ((viewbox_height * viewbox.width / viewbox.height)
>>   		   * iwidth.length);
>> 
>> and not:
>> 
>>   viewbox_width = (viewbox_height * viewbox.width / viewbox.height)
>>     * iwidth.length;
>
> There's nothing wrong with the original style, although I agree that
> using extra parentheses makes it more plausible.  There's no reason to
> be so stringent in insisting on the other style.

The GNU coding standards seem to say something else:

  Insert extra parentheses so that Emacs will indent the code properly.
  For example, the following indentation looks nice if you do it by
  hand,

v = rup->ru_utime.tv_sec*1000 + rup->ru_utime.tv_usec/1000
    + rup->ru_stime.tv_sec*1000 + rup->ru_stime.tv_usec/1000;

  but Emacs would alter it.  Adding a set of parentheses produces
  something that looks equally nice, and which Emacs will preserve:

v = (rup->ru_utime.tv_sec*1000 + rup->ru_utime.tv_usec/1000
     + rup->ru_stime.tv_sec*1000 + rup->ru_stime.tv_usec/1000);

Re: emacs-29 dc78779c0c: Fix SVG scaling (bug#59802)

[Eli Zaretskii]

> From: Po Lu <luangruo@yahoo.com>
> Cc: emacs-devel@gnu.org,  manuel@ledu-giraud.fr
> Date: Sat, 17 Dec 2022 17:51:44 +0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> Our style is to write:
> >> 
> >>   viewbox_width = ((viewbox_height * viewbox.width / viewbox.height)
> >>   		   * iwidth.length);
> >> 
> >> and not:
> >> 
> >>   viewbox_width = (viewbox_height * viewbox.width / viewbox.height)
> >>     * iwidth.length;
> >
> > There's nothing wrong with the original style, although I agree that
> > using extra parentheses makes it more plausible.  There's no reason to
> > be so stringent in insisting on the other style.
> 
> The GNU coding standards seem to say something else:
> 
>   Insert extra parentheses so that Emacs will indent the code properly.
>   For example, the following indentation looks nice if you do it by
>   hand,

Please assume I'm aware of the GCS.

That section explicitly says these are recommendations, not hard
requirements, a little above the text that you cite:

     The rest of this section gives our recommendations for other aspects
  of C formatting style, which is also the default style of the 'indent'
  program in version 1.2 and newer.  It corresponds to the options

       -nbad -bap -nbc -bbo -bl -bli2 -bls -ncdb -nce -cp1 -cs -di2
       -ndj -nfc1 -nfca -hnl -i2 -ip5 -lp -pcs -psl -nsc -nsob

     We don't think of these recommendations as requirements, because it
  causes no problems for users if two different programs have different
  formatting styles.

So please do not push too hard for adopting only one style and nothing
else.  Doing so makes this community less pleasant than it should be.

Re: emacs-29 dc78779c0c: Fix SVG scaling (bug#59802)

[Manuel Giraud]

Hi,

Do you want me to fix this style?
-- 
Manuel Giraud

Re: emacs-29 dc78779c0c: Fix SVG scaling (bug#59802)

[Eli Zaretskii]

> From: Manuel Giraud <manuel@ledu-giraud.fr>
> Cc: Po Lu <luangruo@yahoo.com>,  emacs-devel@gnu.org
> Date: Sat, 17 Dec 2022 18:18:42 +0100
> 
> Hi,
> 
> Do you want me to fix this style?

There's no need.  If we decide to do it, we can do it ourselves.

Re: emacs-29 dc78779c0c: Fix SVG scaling (bug#59802)

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > v = rup->ru_utime.tv_sec*1000 + rup->ru_utime.tv_usec/1000
  >     + rup->ru_stime.tv_sec*1000 + rup->ru_stime.tv_usec/1000;

  >   but Emacs would alter it.  Adding a set of parentheses produces
  >   something that looks equally nice, and which Emacs will preserve:

  > v = (rup->ru_utime.tv_sec*1000 + rup->ru_utime.tv_usec/1000
  >      + rup->ru_stime.tv_sec*1000 + rup->ru_stime.tv_usec/1000);

You're right, these parentheses should be added.  There is no downside
to them, and they will keep the code looking good if it happens to be
reindented.

If I were doing anything with that code, I would add them.

-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)