diff --git a/util/set.lua b/util/set.lua
index a2df669c0..89cd7cf36 100644
--- a/util/set.lua
+++ b/util/set.lua
@@ -75,7 +75,7 @@ function new(list)
 	end
 
 	function set:items()
-		return items;
+		return next, items;
 	end
 
 	function set:remove(item)