When I use R in Emacs through the ESS package, C-c C-c in a .R buffer will send a “block” of code to the inferior R process for evaluation. This was added just a few years ago, but my fingers are now trained to use that key combination for evaluating any block of code. Since I have been learning Emacs Lisp, I decided that a good idea would be to make C-c C-c a binding to eval-defun. I really like how it is working out as I have to redefine my Lisp functions many times!

Just put the following in your .emacs file to get this behavior. However, please note the following from the eval-defun help string, “If the current defun is actually a call to `defvar’ or `defcustom’, evaluating it this way resets the variable using its initial value expression even if the variable already has some other value. (Normally `defvar’ and `defcustom’ do not alter the value if there already is one.)”

(define-key lisp-mode-shared-map "C-cC-c" 'eval-defun)