diff --git a/Lib/std/std_set.i b/Lib/std/std_set.i
index 63d6c5b6c..dee7919db 100644
--- a/Lib/std/std_set.i
+++ b/Lib/std/std_set.i
@@ -21,6 +21,8 @@
   size_type count(const key_type& x) const;
   
 #ifdef SWIG_EXPORT_ITERATOR_METHODS
+  class iterator;
+  class reverse_iterator;
   class const_iterator;
   class const_reverse_iterator;