Re: Debouncing slow mode line constructs (was: Emacs design and architecture. How about copy-on-write?)

[Eli Zaretskii]

> From: Ihor Radchenko <yantar92@posteo.net>
> Cc: Po Lu <luangruo@yahoo.com>, Eli Zaretskii <eliz@gnu.org>, acm@muc.de,
>  incal@dataswamp.org, emacs-devel@gnu.org
> Date: Fri, 22 Sep 2023 10:07:38 +0000
> 
> > Though if we just do this silently, it can hide performance problems, 
> > both discouraging the mode-line authors from fixing them, and creating 
> > odd behaviors (from the user's POV) when something which should change, 
> > doesn't.
> 
> A warning may be displayed when this "debouncing" is activated.

You cannot easily display any warnings from redisplay.