How to best use the display-buffer-function?

How to best use the display-buffer-function?

[Klaus Berndl]

Suppose i want to some checks before `display-buffer'. If the checks are true
then i always want to display the buffer in a special window at my frame, if
the checks fail i want to proceed with standard display-buffer, i.e.
`display-buffer' should choose the window according to all its rules.

Currently i have something like (simplified):

(defun my-display-buffer-function (buffer not-this-window)
  (if (my-pre-checks)
      ;; then display the BUFFER in a special window at the frame
      (my-display-buffer-in-special-window buffer)
    ;; otherwise delegate the buffer-display to the original `display-buffer'
    (let ((display-buffer-function nil))
      (display-buffer buffer not-this-window))))


(setq display-buffer-function my-display-buffer-function)
      
Is this a good way to do this?

Another question: Why a display-buffer-function gets only two args and not
three like the `display-buffer'?

Thanks for comments, hints and help,
Klaus

-- 
Klaus Berndl			mailto: klaus.berndl@sdm.de
sd&m AG				http://www.sdm.de
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