Add note about !rpartial only working on Emacs 24+

bang.el

@@ -143,14 +143,15 @@ Thus function FN should return a collection."
 and returns a fn that takes a variable number of additional ARGS.
 When called, the returned function calls FN with ARGS first and
 then additional args."
-  `(closure (t) (&rest args)
+  (apply 'apply-partially fn args))
-            (apply ',fn ,@(mapcar (lambda (arg) `',arg) args) args)))
 
 (defun !rpartial (fn &rest args)
   "Takes a function FN and fewer than the normal arguments to FN,
 and returns a fn that takes a variable number of additional ARGS.
 When called, the returned function calls FN with the additional
-args first and then ARGS."
+args first and then ARGS.
+
+Requires Emacs 24 or higher."
   `(closure (t) (&rest args)
             (apply ',fn (append args ',args))))