emacs-cleanup.el

#!/usr/bin/env emacs --script
;; should likely be called with 2</dev/null to suppress the various            
;; output to the shell.                                                        

;; I think that this is going to fail non-emacs24 installs, since              
;; 'package isn't installed by default there.  You'll see this error:          
;; "Symbol's function definition is void: package-initialize"                  
;; `brew install emacs` should fix you up, though.                             
(package-initialize)

;; note of course that this will work for non-erlang files, it's just          
;; that I care about erlang and it isn't installed by default. just            
;; add your mode to the to the mode list if you need others                    
(let ((l '(erlang)))
  (dolist (mode l)
    (if (not (package-installed-p mode))
        (package-install mode))))

(defun clean-up-buffer-or-region ()
   "Untabifies, indents and deletes trailing whitespace from buffer or region."
   (interactive)
   (save-excursion
     (unless (region-active-p)
       (mark-whole-buffer))
     (untabify (region-beginning) (region-end))
     (indent-region (region-beginning) (region-end))
     (save-restriction
       (narrow-to-region (region-beginning) (region-end))
       (delete-trailing-whitespace))))

(dolist (file command-line-args-left)
   (find-file file)
   ;; apparently emacs doesn't region-indent to a fixpoint, run this a          
   ;; couple of times. *sigh*                                                   
   (clean-up-buffer-or-region)
   (clean-up-buffer-or-region)
   (clean-up-buffer-or-region)
   (save-buffer))

(kill-emacs 0)