(defcustom delete-selection-mode nil
"Toggle Delete Selection mode.
See command `delete-selection-mode'.
-You must modify via \\[customize] for this variable to have an effect."
+This variable should be set only with \\[customize], which is equivalent
+to using the function `delete-selection-mode'.
:set (lambda (symbol value)
(delete-selection-mode (or value 0)))
:initialize 'custom-initialize-default