Re: split-window-preferred-function

[martin rudalics]

> Because I use
> split-window-preferred-horizontally the diary buffer is shown in a new
> window right of the window holding *scratch*.  Now I eval the second
> `display-buffer' and the right window's buffer is replaced with the
> *Help* buffer.
>
> With `split-height-threshold' set to 20 I get the same behavior.
> Reading the `display-buffer' docstring I think instead of replacing the
> right window's buffer it should instead split the left window
> vertically, cause that's much bigger (61 lines) than the threshold.

You can't see it because you split your windows horizontally.  Try with
vertical splitting.  The earlier mentioned `split-width-threshold' would
handle your case.