set-window-vscroll flaky?

[D. Goel <deego@gnufans.org>]

hello

I can get set-window-vscroll to work from M-: or from inside functions
containing that one single command.

Example:

(defun vel-scroll-up-fractional (acc)
    (set-window-vscroll nil acc))

works just fine when acc is 0.5

However, 
try

(defun vel-scroll-up (amount acc)	
  (scroll-up amount)	
  (set-window-scroll nil acc))

where amount is 0 and acc is 0.5.  (the first one is a dummy line
supposed to do nothing here..)

And the second line seems to have no effect at all.


IOW, I cannot get set-window-scroll to do anything except
interactively in a function all by itself.  Any hints on what i am
doing wrong?  Does it work for anyone?


====================================================

And even when it works in the "function all by itself", it does not
work when that function is called by another function: 

(defun vel-scroll-up (amount acc)	
  (scroll-up amount)	
  (vel-scroll-up-fractional acc))

and then eval (vel-scroll-up 0 0.5) but nothing happens -- the
vel-scroll-up-fractional in the function doesn't seem to do anyting :(

even though M-: (vel-scroll-up-fractional 0.5) works. 



(tried using emacs cvs and emacs21.2) in X where (frame-char-height)
was 14.

    
thanks

DG                                 http://gnufans.net/
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