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

[Juri Linkov]

>>> Maybe a variable 'other-window-scroll-window' whose value could be a
>>> function to get that window.
>>
>> Since there is already the word "window" in the function name,
>> maybe better would be 'other-window-scroll-default' that hints
>> that it overrides the default that is the next window:
>
> Since we already have 'other-window-scroll-buffer' this might be
> confusing.

It's named intentionally to be similar with 'other-window-scroll-buffer'.

> And shouldn't a window, if specified, override a specified buffer?

Its purpose is to override only the part that hard-codes 'next-window'.

> BTW I think we should move 'other-window-for-scrolling' to
> window.el - all it does is call Lisp primitives.  And turn
> scroll_command into 'Fscroll_command' (or, better 'Fscroll_window') so
> things like 'scroll-down' (or, better 'scroll-window-down') and
> 'scroll-other-window-down' could end up in window.el too.  But maybe I'm
> missing some important detail.

I agree it would be nice to move scrolling commands to Lisp.