Re: window groups

[martin rudalics <rudalics@gmx.at>]

 >     One of the problems of integrating ECB into Emacs is to avoid that
 >     "other" Emacs operations interfere with those of ECB (where other
 >     operations include popping up a *help*, *info*, or *backtrace* window).
 >
 > This is an attempt to design a feature to distinguish between the
 > "editing area" and other add-ons, it seems.  Is that right?

It's merely keeping apart IDE specific objects like the editing area or
the IDE's own help system from Emacs specific *help* or *info* buffers.

 > But it also attempts to generalize this by allowing for more than one
 > group.  Do you see a scenario in which having more than one window
 > group in one frame would be used?

All IDEs I know of use just one edit area.  Stefan mentioned that view
areas could be considered a group as well and there are some ECB layouts
where views are split both horizontally _and_ vertically.  In that case
using groups within the view area might be useful.

 > Without such a scenario, we have no
 > basis to think about what operations ought to do in such a case, and thus
 > no basis for the generalization.

One scenario is that of multiple speedbar/window combinations appearing
simultaneously on a frame.  Every such combination would form a separate
window group.

 > Based on what you've said, it seems that there are three kinds of
 > buffers that might appear in something like ECB.  (I am partly guessing,
 > since I have not seen ECB itself.)

I'm guessing as well.

 > * File buffers
 >
 > * Special buffers of ECB
 >
 > * Other buffers such as *Help*, *Info*, and so on.
 >
 > I think the right way to design this feature is to figure out the
 > right thing to do with windows for these three kinds of buffers,
 > and then design an interface to request that.

Yes.

 > But we should not try to make it any more general than that
 > until we have use cases to guide our thinking about them.
 >
 >     By default `display-buffer' does not invoke `split-window' with GROUP
 >     set to t - hence these windows always appear outside the rectangular
 >     ares reserved for group windows.  The same holds for any application
 >     that is not aware of the group the selected window belongs to.
 >
 >     ...
 >
 >     Interactively, `split-window-horizontally' and `split-window-vertically'
 >     would call `split-window' with GROUP set to t iff WINDOW is part of a
 >     group.
 >
 > What about C-x 4 C-f?  If you do that inside ECB, should the new window
 > be part of the ECB group?

I think so but it should be customizable.  The default value would have
to be decided individually for each function.