One common struggle people have with CIDER (and Emacs in general) is that there are way too many keybindings to remember, and some of them require pressing a lot of keys. While there are many ways to address those common problems in Emacs, today I’ll focus on one that’s really simple and CIDER specific.

CIDER’s REPL provides a neat trick inspired by SLIME - REPL shortcuts. They are extremely easy to use - just press , while at the REPL prompt and you’ll get a completing read allowing you run one of the CIDER commands that are bound to REPL shortcuts. Let’s now revisit tidying up our REPL in the context of REPL shortcuts, so you can get a better idea of how this actually works:

CIDER REPL Shortcuts

Note that this example uses the ivy library to display the list of commands that are available. You’ll get different visuals if you’re using some other minibuffer completion library (e.g. ido or icomplete).

If you don’t like using , as the trigger key you can change it to some other key easily. Just put this in your Emacs configuration:

(setq cider-repl-shortcut-dispatch-char ?\!)

The above example changes the trigger key to !. Be careful what you set here, as it shouldn’t be something with which a Clojure form might start. If you selected ', for instance, you’ll have a really hard time entering quoted forms in your CIDER REPL.

There are many commonly used commands that are bound to REPL shortcuts out-of-the-box. You can examine them by selecting help after pressing ,. The shortcuts functionality is user-extensible and you can easily add more commands there:

(cider-repl-add-shortcut "clear-output" #'foo-cmd)
(cider-repl-add-shortcut "clear" #'bar-cmd)
(cider-repl-add-shortcut "clear-banners" #'baz-cmd)

That’s all I have for you today. Simple, sweet and maybe even useful! Keep hacking!