Emacs + paredit
;;; C-M-SPC (select sexp) ;;; C-w (copy ;;; C-y (to paste) (defn some-func [] ;;; )
;;; C-M-k (cut sexp) ;;; C-y (paste sexp) (defn some-func [] ;;; )
M-x clojure-insert-ns-form
M-X clojure-update-ns