diff --git a/src/api/ml/z3.ml b/src/api/ml/z3.ml
index e2fa01478..dafd255f8 100644
--- a/src/api/ml/z3.ml
+++ b/src/api/ml/z3.ml
@@ -119,7 +119,7 @@ let mk_list ( f : int -> 'a ) ( n : int ) =
     if (i >= n) then 
       tail
     else
-      (mk_list' f (i+1) n ((f i) :: tail))
+      (f i) :: (mk_list' f (i+1) n tail)
   in
   mk_list' f 0 n []