bug#12723: 24.2; Improvement: changing text rectangle kill/past and its integration with the kill-ring

[Stefan Monnier]

> It's one thing to leave the rectangle to the user's imagination and
> mental models; it's quite another to actually show that to her.  It's
> quite possible the users today don't even bother looking what's
> between the two corners of the region.  With it highlighted, they
> don't have a chance.

There are several easy ways out:
- Let the user turn off highlighting.
- Let the user not look at the highlighting.
- Don't highlight if the text contains a mix of L2R and R2L (or just
  highlight it in a simpler way that only shows the position of the
  mark).

>> Really, this issue is a complete non-issue
> I obviously disagree.

Then, let's just say that it's a bridge I'm not willing to cross before
we actually get there.

>> we're talking about reflecting on screen what is about to happen, so
>> any problem "on screen" (i.e. in the highlighting) is really due to
>> what's actually going to happen, not to
> It's not carved in stone that a rectangular region must be highlighted
> in the same way as the "normal" region.

I think it should highlight the text actually selected, which doesn't
give us much leeway.

> We could come up with something different, that doesn't suffer from
> the directionality issues, for example.

Fine by me.  All I know is that the rectangle highlighting won't need
complex bidi-aware code.  At most it will have to detect that there's
bidi involved and fallback to another highlighting method.


        Stefan