diff --git a/enum.ml b/enum.ml
index b30c8c06..49bd5583 100644
--- a/enum.ml
+++ b/enum.ml
@@ -170,7 +170,7 @@ let to_list enum =
 let to_rev_list enum =
   let rec fold acc gen =
     let acc', stop =
-      try gen () :: acc, true
+      try let x = gen () in x :: acc, true
       with EOG -> acc, false
     in if stop then acc' else fold acc' gen
   in