Re: mouse-drag-mode-line should maybe use window-tree

[Stefan Monnier]

>     To me the documentation for `adjust-window-trailing-edge' looks like it
>     is doing the same thing as `enlarge-window' with preserve-before set to
>     t.  Am I missing something?
> They are not the same, because adjust-window-trailing-edge will never
> delete a window.

Could you explain the choice of identifier?  I have a hard time understanding
what "adjust-window-trailing-edge" can mean.  What's a trailing edge?

Couldn't we just change the `preserve-before' argument (which is new in
Emacs-22 anyway) instead?

AFAIK in all the cases where the `preserve-before' argument is useful, it's
also useful to avoid deleting windows, but if not, we could have 3 values
for `preserve-before', e.g.:
- nil: same as before.
- `nodelete': behave like adjust-window-trailing-edge.
- t: same as above, but can delete windows.


        Stefan