How can I evaluate something in Emacs init.el file?

Question

Every time I open .clj file, I have to run

M-x cider-jack-in

to enable Clojure auto-completion in code file.

Can I make Emacs automatically run the command when it starts?

Answer 1

Try this:

(require 'cider)
(defun maybe-cider-jack-in ()
  (unless (ignore-errors
            (nrepl-current-connection-buffer))
    (cider-jack-in)))

(add-hook 'clojure-mode-hook 'maybe-cider-jack-in)