bug#51210: Customizable other-window-for-scrolling

[Eli Zaretskii]

> From: Juri Linkov <juri@linkov.net>
> Cc: rudalics@gmx.at,  51210@debbugs.gnu.org
> Date: Mon, 24 Jan 2022 21:42:15 +0200
> 
> >> 'beginning-of-buffer-other-window' has such line at the end:
> >> 
> >>   (recenter '(t))
> >> 
> >> Clearly it makes no sense to recenter at the beginning of the buffer.
> >> So the value '(t)' was intended only to refresh the screen?
> >> Then the same line in 'end-of-buffer-other-window'
> >> should only refresh the screen, not recenter.
> >
> > I'm not sure I understand how all of this is relevant.  Please
> > elaborate.
> 
> Currently the implementation of beginning-of-buffer-other-window
> is this:
> 
> (defun beginning-of-buffer-other-window (arg)
>   (with-selected-window (other-window-for-scrolling)
>     ;; Set point and mark in that window's buffer.
>     (with-no-warnings
>       (beginning-of-buffer arg))
>     ;; Set point accordingly.
>     (recenter '(t))))
> 
> It's not clear what does the last comment mean.
> 'recenter' should set point accordingly to what?
> And what does (recenter '(t)) do at the beginning of the buffer?

It isn't beginning of buffer, it's where (beginning-of-buffer arg)
puts point when ARG is non-nil.  See the doc string of
beginning-of-buffer.