Help with display-buffer-alist

[Ergus]

Hi:

I am trying to mimic somehow the swiper behavior with occur. The first
step for that is to put the occur window always at bottom which was
pretty simple with this:

(add-to-list 'display-buffer-alist ("*Occur*" display-buffer-at-bottom))

But now I want somehow to limit the window height to 10 lines.

With the documentation of display-buffer and display-buffer-alist It
says that there should be (CONDITION . ACTION) where:

ACTION is a cons cell (FUNCTIONS . ALIST), where FUNCTIONS is an
  action function or a list of action functions and ALIST is an
  action alist.  Each such action function should accept two
  arguments: a buffer to display and an alist of the same form as
  ALIST.  See `display-buffer' for details.


So I tried substituting display-buffer-at-bottom with:

(display-buffer-at-bottom . (window-height . 10))

But I am obviously doing something wrong because this just doesn't
work... so the question is: how do I use correctly the
(FUNCTIONS . ALIST) in the extended way?

Thanks in advance,
Ergus...

PD: Maybe another example with this answer may be added to the docstring.