Fix up recent kbd simplification

* lisp/subr.el (kbd): Fix breakage with X-<foo> from previous change.

diff --git a/lisp/subr.el b/lisp/subr.el
index a9669ab750bb516d3c8c1667350a78dc48e02cfc..6bd3b693b8324fd53fabc03b4389e2cbc7d91400 100644 (file)
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -1068,12 +1068,14 @@ and should normally not be needed."
                                     (nreverse lres)
                                     lres))))
       (if (and (not need-vector)
-               (not (memq nil (mapcar (lambda (ch) (<= 0 ch 127))
-                                      (append res nil)))))
+               (not (memq nil (mapcar (lambda (ch)
+                                        (and (numberp ch)
+                                             (<= 0 ch 127)))
+                                      res))))
           (concat (mapcar (lambda (ch)
                             (if (= (logand ch ?\M-\^@) 0)
                                 ch (+ ch 128)))
-                          (append res nil)))
+                          res))
         res))))
 
 (defun undefined ()