(defun add-vendor-directories ()
  (interactive)
  (mapc '(lambda (dir)
           (if (and
                (cadr dir)
                (not (equal (car dir) "."))
                (not (equal (car dir) "..")))
               (add-to-list 'load-path (concat "~/.elisp/vendor/" (car dir)))))
        (directory-files-and-attributes "~/.elisp/vendor")))