Wrong type argument: commandp, ace-window

[yegor256]

I added this to ~/.emacs:

(global-set-key (kbd "M-p") 'ace-window)

Then, restarted emacs and then clicked M-p. I got this at the bottom:

Wrong type argument: commandp, ace-window

This is my Emacs:

$ emacs --version
GNU Emacs 28.2
Copyright (C) 2022 Free Software Foundation, Inc.
GNU Emacs comes with ABSOLUTELY NO WARRANTY.
You may redistribute copies of GNU Emacs
under the terms of the GNU General Public License.
For more information about these matters, see the file named COPYING.

Maybe I missed some installation steps?

[gjw]

I don't think you missed anything - it used to work for me, and at some point last year during upgrades it stopped, with the same error you're getting.