TFL/rules.new.sml

 val term_ref = ref[] : term list ref
 val mss_ref = ref [] : meta_simpset list ref;
 val thm_ref = ref [] : thm list ref;
 val tracing = ref false;
 
-fun say s = if !tracing then (output(std_out,s); flush_out std_out) else ();
+fun say s = if !tracing then prs s else ();
 
 fun print_thms s L = 
    (say s; 
     map (fn th => say (string_of_thm th ^"\n")) L;
     say"\n");