Re: window groups

[Richard M Stallman]

    - Assert that layouts change in a conceivable way.

I am not sure what distinction is meant by "a conceivable way".
Did you mean some other word instead of "conceivable"?

    Technically, group numbers get assigned like window numbers.  It would
    be possible, albeit inefficient, to avoid using numbers: Some group
    identifier must get stored together with each window-configuration.

Can you create an object (even a cons cell) to represent the window
group?  It just has to be unique, different from the cons cell used
for any other window group.

     > It seems unclean that the group disappears if you happen
     > to reduce it to just one window.

    Currently, an invariant requires that group root windows are internal
    Emacs windows.  Hence `delete-window' automatically dissolves a group as
    soon as it has one visible member.  I suppose it wouldn't be difficult
    to relax that invariant.

I think that change is essential for practical use, and also needed
for simplicity.