diff --git a/doc/manual_experimental.md b/doc/manual_experimental.md
index d20695933c..f5e39b768b 100644
--- a/doc/manual_experimental.md
+++ b/doc/manual_experimental.md
@@ -566,6 +566,7 @@ All types for which `nil` is a valid value can be annotated with the
   {.experimental: "notnil".}
 
   type
+    TObj = object
     PObject = ref TObj not nil
     TProc = (proc (x, y: int)) not nil