--- a/demo/more/dlist.urs	Tue Sep 15 09:45:46 2009 -0400
+++ b/demo/more/dlist.urs	Tue Sep 15 10:18:56 2009 -0400
@@ -6,6 +6,7 @@
 val append : t ::: Type -> dlist t -> t -> transaction position
 val delete : position -> transaction unit
 val elements : t ::: Type -> dlist t -> signal (list t)
+val foldl : t ::: Type -> acc ::: Type -> (t -> acc -> signal acc) -> acc -> dlist t -> signal acc
 
 val render : ctx ::: {Unit} -> [ctx ~ body] => t ::: Type
              -> (t -> position -> xml (ctx ++ body) [] [])