1 files changed, 1 insertions, 1 deletions

diff --git a/edit-lens/src/Control/DFST.lhs b/edit-lens/src/Control/DFST.lhs
index 94df533..9bd1629 100644
--- a/edit-lens/src/Control/DFST.lhs
+++ b/edit-lens/src/Control/DFST.lhs
@@ -46,7 +46,7 @@ toFST :: forall state input output. (Ord state, Ord input, Ord output) => DFST s
 toFST DFST{..} = flip execState initialFST $ forM_ (Map.toList stTransition) handleTransition
   where
     initialFST = FST
-      { stInitial = (stInitial, Nothing)
+      { stInitial = Set.singleton (stInitial, Nothing)
       , stTransition = Map.empty
       , stAccept = Set.map (, Nothing) stAccept
       }