Re: [Emacs-diffs] /srv/bzr/emacs/trunk r99831: Scrolling commands which does not signal errors at top/bottom.

[Juri Linkov]

>> `mwheel-scroll' disobeys `scroll-preserve-screen-position' too.
>
> I would consider that a bug, too. The docstring for
> `scroll-preserve-screen-position' does talk about "scroll commands".
> The reason the option exists, I think, is because some of us find the
> non-preserving behavior quite unbearable (I used Mikael Sjödin's
> pager.el for years because I found the standard scroll-(up|down)
> commands almost unusable).

I have a 1997-year copy of pager.el (not sure if later versions exist).
It contains the variable `pager-keep-column-commands' that defines
a list of scrolling commands that keep the current column.

Maybe `scroll-up-command' and `scroll-down-command' should use a similar
list.  And then `mwheel-scroll' and scroll-(up|down)-line should call
`scroll-(up|down)-command' instead of `scroll-(up|down)'.

>> I think
>> it would be wrong to add all possible scrolling commands to this code:
>
> Why? Perhaps it should be implemented differently, but that's not the
> same as being "wrong".

By "wrong" I meant that window.c is the wrong place to implement this.

-- 
Juri Linkov
http://www.jurta.org/emacs/