Re: delete-selection-mode (was: Put scroll-bar on right by default on UNIX.)

[Alan Mackenzie <acm@muc.de>]

Hi, Stephen!

On Thu, Mar 18, 2010 at 01:40:14PM +0900, Stephen J. Turnbull wrote:
> Alan Mackenzie writes:

>  > The answer is to ask them why they want this.  C-w is easy to type,
>  > as is <delete>.

> I can't speak for "them," but I want DEL to *delete* the region
> because *kill-region* is very often *not* what I want.  Ie, I do not
> want the deleted text on the kill ring.

OK, that's an interesting point, but I'm not sure how connected it is to
d-s-m.  Ideally, one wants a keybinding for `delete-region' (which is
already a command), but there aren't any short enough ones free, really;
maybe C-M-x, or something like that.  I also think that the distinction
between kill-region and delete-region would be more confusing than
helpful to a beginner.

> It's also often useful to me to have the text being replaced on screen
> as I begin to type the replacement text, rather than delete and insert
> separately.  These small differences really matter, a microsecond here,
> a half-second there, it starts to add up to a noticably smoother
> experience.

OK.  The penalty for that convenience is having your region explode and
disappear when you accidentally type a self-insert character (or arrow
key).  This might happen if you hit the x before the M in M-x, or
something like that.  Or, you might regionify a defun with C-M-h for some
reason and accidentally lose it.

Clearly the convenience benefit dominates for you; the accidental
explosion hazard dominates for me (in non-Emacs environments, where I
can't disable the (mis)feature).  I've no reason to suspect I'm unusual
here.

It's "obviously" useful to be able to type extra text into an already
"existing" region.  The region is used for many things other than just
being deleted.

>  > delete-select-mode is such an irritating distraction

> In Emacsen without zmacs-regions/transient-mark-mode on, I agree
> strongly.  In Emacs with t-m-m, I disagree strongly.

> Yes, veteran users will find the change in defaults (both t-m-m and
> delsel, whether simultaneously or sequentially) an irritating
> distraction.  There should be a way for veterans to tell Emacs "Read
> my lips: No New UI Features", but sadly enough, there isn't.  But vets
> know how to turn off such annoyances quickly and permanently.

Do they?  How do we know there aren't lots of "veteran" users who don't
really know how to configure the thing?

I think we should also distinguish between pure new UI features, and
those that actively interfere with established usage.  My view is that we
should never make something default in Emacs if it's likely to provoke
the angry reaction "How do I disable this *!£$ing thing?".
delete-select-mode falls into this latter category.  So does
transient-mark-mode.

>  > that it should only be enabled for those who really, truly want it.

> Which is almost everybody with either no experience or the leisure to
> spend a very frustrating 3 days (what it took me to adapt to
> zmacs-regions, 15 years ago) to 1 week retraining muscle memory.
> t-m-m + delsel is a simple, global improvement as a default *for the
> new user*.

I think you might be exaggerating a bit for this particular feature.
It's of the same order of magnitude as swapping the 'z' and 'y' keys (as
one does in moving between English and German keyboard layouts) - it's a
slight irritation, not really a big thing.

Is there any evidence that delete-select-mode is instrinsically a good
thing, disregarding the fact that it has become common?

>  > Emacs isn't about taking things for granted.  It's about efficiency,
>  > about minimising keystrokes, about not getting in the users' way.
>  > How about improving the documentation/menu-settings/ whatever so
>  > that these beginners find what they're looking for?

[ .... ]

> Why not give them [Emacs newbies] these very efficient patterns that
> have proven themselves not only in software for the braindead, but in
> daily usage by thousands of Emacs users as well?

Where is the proof that d-s-m has proven itself efficient, rather than
being mainly an irritation?  That's a genuine question, not a rhetorical
one.

One reason people might have come to Emacs is to escape the (to them)
deity-awful key sequences they've been forced to use up to now.  It is
surely good to offer them an alternative.

>  > No.  We do not want to send Emacs down the slippery slope towards
>  > lowest common denominator editors.  We want to encourage Emacs
>  > users to use Emacs efficiently, taking advantage of its many
>  > features.

> Of which t-m-m plus delsel is one.  I'm only sad that you aren't able
> to take advantage of it. :^)

Me too!

-- 
Alan Mackenzie (Nuremberg, Germany).