Subject: Re: bug#23478: 25.0.93; Mouse region selection asymmetry

From: Stephen Berman <[email-masked]>
Date: Thu, 07 Jul 2016 18:22:42 +0200

On Thu, 07 Jul 2016 18:29:54 +0300 Eli Zaretskii <[email-masked]> wrote:

>> From: Stephen Berman <[email-masked]>
>> Cc: [email-masked],  [email-masked]
>> Date: Thu, 07 Jul 2016 14:08:32 +0200
>> 
>> >> +(defcustom mouse-select-region-backward nil
>> >
>> > I'd name it mouse-select-region-scroll-backward.
>> 
>> Using "scroll" in the name suggests that the main purpose of this
>> variable is to control scrolling backward, but it only controls the
>> final position of point, and scrolling is a by-product of that which
>> only happens if necessary.  Given that, do you still prefer to have
>> "scroll" in the name?
>
> I'm not great at naming symbols, so I don't insist.  However, the
> original name seemed slightly misleading: it could be interpreted as
> if the selection will be made backward, which is incorrect.  And since
> I know that the "select-region" belongs to "mouse", I'm left wondering
> what is "backward" about.

What do you understand by "selection backward"?  My intention was to
indicate that this variable controls selecting the region when you
double-click at region-end; in this it is indeed selection backward from
point, though I admit that the phrasing is not elegant.

> Do you see my problem with the name?  If so, perhaps you can suggest a
> better one.

I don't yet see your problem, because I don't know how you interpreted
"selection backward".  I did struggle a bit with the name, though, and
am not thrilled with it.  But if no one comes up with a better name and
you find this one unsuitable, I can certainly live with
mouse-select-region-scroll-backward.

>> One somewhat embarassing aspect of describing this option is that is
>> makes the default asymmetrical behavior painfully obvious without
>> providing a rationale for it (and I don't know of any).  I suppose we
>> could add "for historical reasons" after "by default"....
>
> I don't think it's needed: since point doesn't move, no scrolling
> should be expected.

What's not needed: the phrase "for historical reasons", a rationale for
the asymmetrical behavior, or any description of the user option?  In
other words, are you saying the doc changes in the patch are acceptable?

Steve Berman