Re: [ELPA] Brief v5.90: neighboring window merge on deletion

[martin rudalics]

> Now if we use Brief `<F4> <right>' command from the `S' (`S'elected)
> window to delete the `T' (`T'arget) window, it will reconstruct the
> windows by deleting all the windows keeping only `S', then re-split
> the frame by first split horizontally the window, then reconstruct
> the bottom two windows achieving the desired layout:
>   _____
> |_S___|
> |__|__|
>
> This reconstruction happens instantaneously so it's almost not
> noticeable to users unless on slow terminals.  Sometimes in X windows
> the affected window boundary might shift a little if the original layout
> is complicated or is 1-character in width/height difference between
> `S' and `T' (my default 1-character tolerance setting).

Your reconstruction kills all previously live windows but 'S' and
produces new ones.  This means that buffer overlays with a 'window'
property will not work correctly in any of the new ones.  Moreover, if
such windows were stored in Lisp variables, they would be considered
dead although they apparently still exist like the ones in the lower
part of your frame.

> This also explains why the following `circular' layout is not possible
> as we can't find a split line either vertically or horizontally.
>   ______
> |____| |
> | |__|_|
> |_|____|

Emacs frames are guillotine-patterns.  Each window split corresponds to
a non-intersecting guillotine-cut of the parent window.

martin