bug#15899: 24.3.50; regression: `region' overlay is lower priority than default

[Jarek Czekalski <jarekczek@poczta.onet.pl>]

W dniu 2013-11-16 11:42, Eli Zaretskii pisze:
> Every freedom must have its limits. "Your freedom to swing fists ends 
> where my nose begins." (Yes, I know I'm lecturing, but so did you.)

Sorry if you didn't like my tone. I tried to make a general point and 
justify it well. On the other hand, I don't mind lecturing like yours, 
if that's what we call lecturing here.

> So I think we should turn the table and ask why would a user need to
> have this freedom now, and only give that freedom if the cause
> justifies it.

Good point. I would do it just for the sake of flexibility, which Emacs 
should be proud of. We may not predict in what way people will want to 
user overlays. And some of them may be silently disappointed if 
flexibility of overlays is not sufficient. They even won't complain 
about it, so we may never hear such a request. But if flexibility is 
achieved, there may be silent happy users. That's a benefit.

Introducing a new feature needs considering pros and cons. Personally I 
don't see enough cons. Dmitri's answer presents ways to deal with 
potential problems. Good documentation would be the most important 
weapon. Something like: "It is strongly suggested not to specify a 
priority higher than ..., because it will cause problems with displaying 
selection boundaries."

An example of such need just came to my mind. A temporary overlay which 
highlights for a second the words spoken by a user through a microphone.

So if I were to decide, I would say: freedom and flexibility!

Sorry again for lecturing. And being pathetic too :)

Jarek