On 2016-07-03 18:34, Richard Stallman wrote:
> > > Is there a standard way to run a function after each redisplay cycle?
> 
> > No, not that I know of.
> 
> It is asking for trouble, since if there is any bug in it or confusing
> behavior, you will get totally screwed.

Much more than with a pre- or post-command-hook? We could have the same logic for errors:

    If an unhandled error happens in running this hook,
    the function in which the error occurred is unconditionally removed, since
    otherwise the error might happen repeatedly and make Emacs nonfunctional.

Clément.