From: Kim F. Storm <storm@cua.dk>
Date: Mon, 20 Jun 2005 21:41:34 +0000 (+0000)
Subject: (add-to-ordered-list): Test membership with eq.  Simplify.
X-Git-Tag: emacs-pretest-22.0.90~8791
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=ef1eef065fadb7ca04d97d455162f2ec45f175e9;p=emacs.git

(add-to-ordered-list): Test membership with eq.  Simplify.
---

diff --git a/lisp/subr.el b/lisp/subr.el
index f913e984b88..f0b8f9e96a7 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -960,12 +960,11 @@ other hooks, such as major mode hooks, can do the job."
 
 (defun add-to-ordered-list (list-var element &optional order)
   "Add to the value of LIST-VAR the element ELEMENT if it isn't there yet.
-The test for presence of ELEMENT is done with `equal'.
+The test for presence of ELEMENT is done with `eq'.
 
 The resulting list is reordered so that the elements are in the
-order given by each element's numeric list order.
-Elements without a numeric list order are placed at the end of
-the list.
+order given by each element's numeric list order.  Elements
+without a numeric list order are placed at the end of the list.
 
 If the third optional argument ORDER is non-nil, set the
 element's list order to the given value.
@@ -979,16 +978,16 @@ The return value is the new value of LIST-VAR."
       (put list-var 'list-order
            (setq ordering (make-hash-table :weakness 'key :test 'eq))))
     (when order
-      (puthash element order ordering))
-    (add-to-list list-var element)
+      (puthash element (and (numberp order) order) ordering))
+    (unless (memq element (symbol-value list-var))
+      (set list-var (cons element (symbol-value list-var))))
     (set list-var (sort (symbol-value list-var)
 			(lambda (a b)
 			  (let ((oa (gethash a ordering))
 				(ob (gethash b ordering)))
-			    (cond
-			     ((not oa) nil)
-			     ((not ob) t)
-			     (t (< oa ob)))))))))
+			    (if (and oa ob)
+				(< oa ob)
+			      oa)))))))
 
 
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