Explain about ordering of alternatives in `choice'.

lisp/ChangeLog

@@ -1,3 +1,22 @@
+2002-11-29  Richard M. Stallman  <rms@gnu.org>
+
+	* mail/rmail.el (rmail-convert-to-babyl-format):
+	Make search for message delimiter case-sensitive.
+
+	* simple.el (yank-window-start): New variable.
+	(yank): Record yank-window-start
+	(yank-pop): Use yank-window-start.
+
+	* info.el (Info-additional-directory-list): Doc fix.
+
+	* indent.el (indent-according-to-mode, indent-region): Doc fix.
+
+	* tooltip.el (tooltip-gud-tips-p): Doc fix.
+
+	* eshell/em-script.el: Require eshell.
+
+	* eshell/esh-ext.el, eshell/em-cmpl.el: Require esh-util.
+
 2002-11-29  Kim F. Storm  <storm@cua.dk>
 
 	* mwheel.el: Avoid accidental yanking of text while scrolling with
@@ -273,7 +292,7 @@
 	* emacs-lisp/autoload.el (update-autoloads-from-directories):
 	Sort the list of files with no autoloads.
 
-2002-11-16  Alan Shutko  <ats@acm.org>
+2002-11-16  Alan Shutko  <Rats@acm.org>
 
 	* calendar/diary-lib.el (list-diary-entries): Pass a marker
 	indicating source of entry to add-to-diary-list.

lispref/customize.texi

@@ -661,6 +661,19 @@ In any alternative for which @code{nil} is not a valid value, other than
 a @code{const}, you should specify a valid default for that alternative
 using the @code{:value} keyword.  @xref{Type Keywords}.
 
+If some values are covered by more than one of the alternatives,
+customize will choose the first alternative that the value fits.  This
+means you should always list the most specific types first, and the
+most general last.  Here's an example of proper usage:
+
+@example
+(choice (const :tag "Off" nil) symbol (sexp :tag "Other"))
+@end example
+
+@noindent
+This way, the special value @code{nil} is not treated like other
+symbols, and symbols are not treated like other Lisp expressions.
+
 @item (radio @var{element-types}@dots{})
 This is similar to @code{choice}, except that the choices are displayed
 using `radio buttons' rather than a menu.  This has the advantage of