tuned -- fewer warnings;

--- a/src/Tools/Haskell/Haskell.thy	Sat Jan 29 15:24:05 2022 +0000
+++ b/src/Tools/Haskell/Haskell.thy	Mon Jan 31 10:01:50 2022 +0100
@@ -3662,7 +3662,7 @@
   _typ :: Bytes,
   _value :: Bytes }
 
-data T = Options (Map Bytes Opt)
+newtype T = Options (Map Bytes Opt)
 
 
 {- check -}