Emacs microhabit: Switching windows with windmove, ace-window, and ace-jump

Posted: - Modified: | emacs

When I work with a large monitor, I often divide my Emacs frame (what most people call a window) into two or more windows (divisions within a frame). I like this more than dealing with multiple Emacs frames, even if I could spread those frames across multiple monitors. I find it easier to manage the windows using keyboard shortcuts than to manage the tiling and display of frames.

One of the Emacs micro-habits I'm working on is getting better at switching between windows. When there are only two windows, C-x o (other-window) works just fine. However, when there are three or more, it can take a few repetitions of C-x o to get to where I want. I could get around that by binding other-window to M-o instead, replacing the default keymap for that. Or I could try to get the hang of other ways to move around.

Here's an 8-minute video showing windmove, ace-window, and ace-jump:

https://www.youtube.com/watch?v=nKCKuRuvAOw&list=UUlT2UAbC6j7TqOWurVhkuHQ

Windmove lets you move around with cursor keys, if you set up the appropriate keyboard shortcuts. Ace-window works like ace-jump. In addition, you can use C-u to swap windows and C-u C-u to delete windows. Ace-jump works across windows, so that's handy too.

Here's my relevant code snippet for Windmove. I changed this to use define-key instead of bind-key.

(defvar sacha/windmove-map (make-sparse-keymap))
(define-key sacha/windmove-map "h" 'windmove-left)
(define-key sacha/windmove-map "t" 'windmove-up)
(define-key sacha/windmove-map "n" 'windmove-down)
(define-key sacha/windmove-map "s" 'windmove-right)
(define-key sacha/windmove-map "[left]" 'windmove-left)
(define-key sacha/windmove-map "[up]" 'windmove-up)
(define-key sacha/windmove-map "[down]" 'windmove-down)
(define-key sacha/windmove-map "[right]" 'windmove-right)
(key-chord-define-global "yy"     sacha/windmove-map)

Here's the cheat sheet I made for myself:

2015-01-12 Emacs microhabit - window management -- index card #emacs

2015-01-12 Emacs microhabit – window management – index card #emacs

And here's a simpler reference that you can personalize with your own shortcuts:

2015-01-18 Emacs microhabit - Switching windows -- index card #emacs #microhabit

2015-01-18 Emacs microhabit – Switching windows – index card #emacs #microhabit

Naturally, after recording the video, I thought of a better way to manage my windows. I took advantage of the def-repeat-command that abo-abo posted on (or emacs so that I could repeat keybindings easily. I modified the function to accept nil as the first value if you don't want the keymap to run a command by default, and to use kbd for the keybinding definitions.

  (defun sacha/def-rep-command (alist)
    "Return a lambda that calls the first function of ALIST.
It sets the transient map to all functions of ALIST,
allowing you to repeat those functions as needed."
    (lexical-let ((keymap (make-sparse-keymap))
                  (func (cdar alist)))
      (mapc (lambda (x)
              (when x
                (define-key keymap (kbd (car x)) (cdr x))))
            alist)
      (lambda (arg)
        (interactive "p")
        (when func
          (funcall func arg))
        (set-transient-map keymap t))))

Here's my new binding for yy. It lets me bounce on y to use other-window as normal, use the arrow keys to move between windows thanks to windmove, and use ace-window as well: h is the regular ace-window, s swaps, and d deletes.

(key-chord-define-global "yy"   
      (sacha/def-rep-command
       '(nil
         ("<left>" . windmove-left)
         ("<right>" . windmove-right)
         ("<down>" . windmove-down)
         ("<up>" . windmove-up)
         ("y" . other-window)
         ("h" . ace-window)
         ("s" . (lambda () (interactive) (ace-window 4)))
         ("d" . (lambda () (interactive) (ace-window 16)))
         )))

Neat, eh?

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