anchor.diff:  
   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   %% utilities
  -
  -print_state(M,CLD) ->
  -  print_term(expand_recs(M,CLD)).
   
   print_term(Term) -> 
     print_term(group_leader(),Term).
  
positive.code: 
  safer(LD,_,[stop|_]) ->
    {stop,shutdown,LD};
  safer(LD,F,[print_state|As]) ->
    print_state(LD#ld.mod,last(As)),
    safe_default(F,LD);
  safer(LD,F,As) ->
    case erlang:function_exported(LD#ld.mod,F,length(As)) of
      false-> safe_default(F,LD);
  
negative.code:   end.
  
  safe_reply(handle_call,LD,{Reply,CLD}) -> {reply,Reply,LD#ld{cld=CLD}};
  safe_reply(handle_call,LD,CLD)         -> {noreply,LD#ld{cld=CLD}};
  safe_reply(handle_cast,LD,CLD)         -> {noreply,LD#ld{cld=CLD}};
  safe_reply(handle_info,LD,CLD)         -> {noreply,LD#ld{cld=CLD}};
  safe_reply(_          ,LD,CLD)         -> {ok,LD#ld{cld=CLD}}.
  
  safe_default(handle_call,LD) -> {reply,ok,LD};
  safe_default(handle_cast,LD) -> {noreply,LD};
  