bug#45688: 28.0.50; New action for display-buffer?

[Lars Ingebrigtsen]

Reading this:

https://www.jwz.org/blog/2021/01/very-much-do-not-have-my-emacs-setup-just-how-i-like-it/

I was curious how XEmacs did this command, so I installed XEmacs.  If
there's two (or one) window, the command works the same in Emacs and
XEmacs, but it's interesting what XEmacs does when there's more than two
windows: It cycles the windows.

Say you start with this:

-----
buf 1
-----
buf 2
-----
buf 3
-----

and you're in buf 1.  `M-x display-buffer RET RET' then gives you:

-----
buf 1
-----
buf 4
-----
buf 3
-----

Repeat, and:

-----
buf 1
-----
buf 4
-----
buf 2
-----

Repeat, and:

-----
buf 1
-----
buf 3
-----
buf 2
-----

Repeat, and:

-----
buf 1
-----
buf 3
-----
buf 4
-----

Repeat, and:

-----
buf 1
-----
buf 2
-----
buf 4
-----

That is, it cycles the windows.  If there are more windows, it'll go
through all the other windows in order, choosing the
least-recently-switched-to window.

This does indeed seem quite nice, and apparently none of the built-in
actions has this effect?

Action functions and the action they try to perform are:
 ‘display-buffer-same-window’ -- Use the selected window.
 ‘display-buffer-reuse-window’ -- Use a window already showing
    the buffer.
 ‘display-buffer-in-previous-window’ -- Use a window that did
    show the buffer before.
 ‘display-buffer-use-some-window’ -- Use some existing window.
 ‘display-buffer-pop-up-window’ -- Pop up a new window.
 ‘display-buffer-below-selected’ -- Use or pop up a window below
    the selected one.
 ‘display-buffer-at-bottom’ -- Use or pop up a window at the
    bottom of the selected frame.
 ‘display-buffer-pop-up-frame’ -- Show the buffer on a new frame.
 ‘display-buffer-in-child-frame’ -- Show the buffer in a
    child frame.
 ‘display-buffer-no-window’ -- Do not display the buffer and
    have ‘display-buffer’ return nil immediately.

So I wonder whether it would make sense to add this. 



In GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.23, cairo 
version 1.16.0)
 of 2020-12-31 built on xo
Repository revision: 72b8430fea79cb1ebb8c3652babf42a12569ab8a
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12008000
System Description: Debian GNU/Linux bullseye/sid


-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no