Test for an up-to-date Custom library when byte-compiling, and issue
an informative message when one cannot be found, as is the case with a
vanilla Emacs 19.34 (and NTEmacs 19.34).
diff --git a/Misc/python-mode.el b/Misc/python-mode.el
index f878576..140d3c0 100644
--- a/Misc/python-mode.el
+++ b/Misc/python-mode.el
@@ -30,6 +30,8 @@
;; you may need to acquire the Custom library. Please see
;; <http://www.python.org/ftp/emacs/> for details.
+;; You will want to byte-compile this file.
+
;; python-mode.el is currently distributed with XEmacs 19 and XEmacs
;; 20. Since this file is not GPL'd it is not distributed with Emacs,
;; but it is compatible with 19.34 and the current 20 series Emacsen.
@@ -80,7 +82,24 @@
(require 'custom)
(eval-when-compile
- (require 'cl))
+ (require 'cl)
+ (require 'custom)
+ ;; Stock Emacs 19.34 has a broken/old Custom library that does more
+ ;; harm than good
+ (or (fboundp 'defcustom)
+ (error "STOP! STOP! STOP! STOP!
+
+The Custom library was not found or is out of date. A more current
+version is required. Please download and install the latest version
+of the Custom library from:
+
+ <http://www.dina.kvl.dk/~abraham/custom/>
+
+See the Python Mode home page for details:
+
+ <http://www.python.org/ftp/emacs/>
+")))
+
;; user definable variables