Add set iterator
diff --git a/src/hb-set.cc b/src/hb-set.cc
index 7103bcd..5045386 100644
--- a/src/hb-set.cc
+++ b/src/hb-set.cc
@@ -182,3 +182,10 @@
 {
   return set->get_max ();
 }
+
+hb_bool_t
+hb_set_next (hb_set_t       *set,
+	     hb_codepoint_t *codepoint)
+{
+  return set->next (codepoint);
+}