diff -r ac146fc38b51 -r 396d4d6a1594 src/Tools/code/code_haskell.ML
--- a/src/Tools/code/code_haskell.ML	Wed May 06 16:01:06 2009 +0200
+++ b/src/Tools/code/code_haskell.ML	Wed May 06 16:01:06 2009 +0200
@@ -261,7 +261,7 @@
                     val vars = init_syms
                       |> Code_Printer.intro_vars (the_list const)
                       |> Code_Printer.intro_vars vs;
-                    val lhs = IConst (classparam, ([], tys)) `$$ map IVar vs;
+                    val lhs = IConst (classparam, (([], []), tys)) `$$ map IVar vs;
                       (*dictionaries are not relevant at this late stage*)
                   in
                     semicolon [