Re: window-resizable confusion

[martin rudalics]

>   (window-resizable WINDOW DELTA &optional HORIZONTAL IGNORE TRAIL NOUP
>   NODOWN)
>
>   Return DELTA if WINDOW can be resized vertically by DELTA lines.
>   ...
>   Optional argument NODOWN non-nil means don't check whether WINDOW
>   and its child windows can be resized.
>
> I don't understand the NODOWN argument.  When NODOWN is non-nil, the
> docstring says the function doesn't check whether WINDOW can be resized.
> So what else is it doing instead?

The answer to the question whether a window W can be resized consists of
two parts - a "down" part and an "up" part.  In the down part I check
whether resizing would violate the min-/fixed-size restrictions of W or,
if W is internal, the leaf windows of W's subtree.  In the up part I
check whether resizing W would violate the min-/fixed-size restrictions
of W's siblings, its parent's siblings, ...

NODOWN non-nil means do not perform the down part because it's not
needed, for example, when W is deleted or I already know that W or its
subwindows can be given the requested size.

The doc-string is obviously silly in this respect.  If you can do any
better, please try.  Otherwise, I'll fix it somehow.

martin