diff -r 6ddbfad8ca20 -r 406a85a25189 src/Tools/Code/code_haskell.ML
--- a/src/Tools/Code/code_haskell.ML	Fri Sep 20 13:30:55 2024 +0200
+++ b/src/Tools/Code/code_haskell.ML	Fri Sep 20 14:28:13 2024 +0200
@@ -23,7 +23,7 @@
   "{-# LANGUAGE " ^ commas language_extensions ^ " #-}";
 
 val language_params =
-  space_implode " " (map (prefix "-X") language_extensions);
+  implode_space (map (prefix "-X") language_extensions);
 
 open Basic_Code_Symbol;
 open Basic_Code_Thingol;