rx fix for `not'

[Dave Love]

This is needed to distinguish the cases in the cond below it if you
have the default value of case-fold-search.

2004-01-13  Dave Love  <address@hidden>

        * emacs-lisp/rx.el (rx-not): Bind case-fold-search.

--- rx.el~      Thu Jan  8 18:32:56 2004
+++ rx.el       Mon Jan 12 21:14:35 2004
@@ -348,7 +348,8 @@
 (defun rx-not (form)
   "Parse and produce code from FORM.  FORM is `(not ...)'."
   (rx-check form)
-  (let ((result (rx-to-string (cadr form) 'no-group)))
+  (let ((result (rx-to-string (cadr form) 'no-group))
+       case-fold-search)
     (cond ((string-match "\\`\\[^" result)
           (if (= (length result) 4)
               (substring result 2 3)