src/Pure/ML-Systems/smlnj.ML

     Control.Print.printDepth := dest_int n div 2;
     Control.Print.printLength := dest_int n);
   val _ = default_print_depth 10;
 end;
 
-val ml_make_string = "(fn _ => \"?\")";
+fun ml_make_string (_: string) = "(fn _ => \"?\")";
 
 
 (*prompts*)
 fun ml_prompts p1 p2 =
   (Control.primaryPrompt := p1; Control.secondaryPrompt := p2);