anchor.diff:    gen_server:start_link({local, Mod}, ?MODULE, {Mod,Args}, []).
   
   stop(Mod) -> 
  -  try gen_server:cast(Mod,stop) 
  -  catch exit:{noproc,_} -> ok
  -  end.
  +  cast(Mod,stop).
  +
  +shutdown(Mod) -> 
  +  cast(Mod,shutdown).
   
   get_state(Mod,Field) ->
     case proplists:is_defined(Field,State = get_state(Mod)) of
  
positive.code: %% implementation
  
  safer(LD,_,[stop|_]) ->
    {stop,shutdown,LD};
  safer(LD,F,[get_state|As]) ->
    CLD = last(As),
  
negative.code: safe_reply(handle_info,LD,CLD)         -> {noreply,LD#ld{cld=CLD}};
  safe_reply(_          ,LD,CLD)         -> {ok,LD#ld{cld=CLD}}.
  
  safe_default(init,LD)        -> exit(LD);
  safe_default(handle_call,LD) -> {reply,ok,LD};
  safe_default(handle_cast,LD) -> {noreply,LD};
  safe_default(handle_info,LD) -> {noreply,LD};
  