Re: Tabs are ready? -> Let us give a definition of tabs.

[martin rudalics]

> The tabs should be a defined as a list of objects (of type 'tab) in the
> struct frame.

Why do you want to introduce such a restriction?  If people want to
specify tabs on a window- or buffer-local basis they should be allowed
to do so.

> Other example: a tab that switches to a buffer assoc with a file, like
> /root/.emacs
>
>  - initialization event is defined so:
>
>    -- erase all windows, and keep 1 window ( delete-other-windows )

This is an example where frame-only tabs are hardly useful.  Switching
to a buffer should not delete other windows.

>    -- memorize window configuration into a variable 'OLD-window-config
> inserted in the assoc list of the tab

This is an example where associating tabs with frames seems useful.

> Note that it require not too much work at C level, and it gives a huge
> number of possibilities of defining tabs, exactly as the 2 principles says.

In which sense do your tabs differ from menu or toolbar elements?  You
can easily add a menu element to save the current window configuration
or pick one of a list of earlier saved configurations to restore that.

martin