Re: delete-selection-mode

[Stefan Monnier]

> I also think that the distinction between kill-region and
> delete-region would be more confusing than helpful to a beginner.

Indeed.

> 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.

These are very valid concerns, and even if we don't enable delsel by
default, I think we should try and come up with ways to reduce the pain.
E.g. making sure that you can revert the damage with `undo' (e.g. the
delsel behavior should only affect buffer where undo is enabled; and
maybe undoing a self-insert which also deleted the region might undo the
self-insert, undo the delete-region *and* re-activate the region).

> 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.

Maybe there should be more ways than C-g to deactivate the region:
Currently, self-insert is one such way, but with delsel that extra way
is removed.

>> > 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.

delsel only applies to active regions, so it shouldn't affect users when
t-m-m is disabled.  That would seem to imply that overall you disagree
strongly with "delete-select-mode is such an irritating distraction".
Yet, your message seems to indicate otherwise.  What am I missing?

> 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.

Many things have fallen into this category in the past:
- X11 (need to use -nw).
- menu-bar
- tool-bar
- scroll-bar
- fringes
- blinking-cursor
- t-m-m
- font-lock
- mouse-1-click-follows-link
- "prettification" of info buffers
Luckily, we don't have to care too much about those conservative
veterans, because honestly their only alternative is Emacs-NN (where NN
is smaller than some threshold): pretty much all other applications
impose changes to their UI at a faster pace than Emacs ;-)

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

For DEL, I think it is very natural, yes.  For self-insert, I'm not
really sure: I haven't been annoyed by it, but I haven't used it
much either.


        Stefan