(gnus-union): New function.

diff --git a/lisp/gnus-util.el b/lisp/gnus-util.el
index de5e352..d7a81f8 100644 (file)
--- a/lisp/gnus-util.el
+++ b/lisp/gnus-util.el
@@ -1005,6 +1005,15 @@ ARG is passed to the first function."
                           (car (symbol-value sym))))))
        hashtb))))
 
+(defun gnus-union (a b)
+  "Add members of list A to list B
+if they are not equal to items already in B."
+  (if (null a)
+      b
+    (if (member (car a) b)
+       (gnus-union (cdr a) b)
+      (gnus-union (cdr a) (cons (car a) b)))))
+
 (provide 'gnus-util)
 
 ;;; gnus-util.el ends here