Re: Redisplay hook

[Stefan Monnier]

> Blocking input is not enough (and is just a workaround for problems
> you had, anyway).  But before we discuss this seriously, I have a
> feeling that such a hook was already discussed in the past, and we
> found it unnecessary and/or dangerous.  Stefan, do you remember
> something like that?

I don't have a clear recollection either, sorry.

I guess part of the question is what would be the use of such a hook.
The difference between a pre-redisplay-hook and a
post-redisplay-hook is not very large since most of the result of
redisplay is "invisible" to Elisp.  The main differences I can think of
would be:
- jit-lock stuff, in case you want to see the buffer after jit-locking.
  but it seems you can just as well hook into jit-lock to get
  that result.
- scrolling, in case you want to react to changes in the user-visible
  window-start/end.

Of course the use could be fairly tricky, with risks of the
post-redisplay-hook causing further redisplay-cycle ad-nauseam, but we
already have this problem with the window-scroll-functions, IIRC.


        Stefan