anchor.diff:  incoming(<<Tok:4/binary, Data/binary>>, St) ->
       case check_token(Tok, Data, St) of
   	true ->
  -	    ?dbg("incoming token verified~n"
  -		 "Data = ~p~n", [Data]),
  +	    ?debug("incoming token verified~n"
  +		   "Data = ~p~n", [Data]),
   	    Data;
   	false ->
  -	    ?dbg("bad incoming token~n", []),
  +	    ?debug("bad incoming token~n", []),
   	    error(bad_token)
       end.
   
  
positive.code: 
  -compile(export_all).
  
  -record(data, {
  	  id,
  	  chal,
  
negative.code: %% 	theirs = #data{key = TheirKey}}.
  
  init(Opts) ->
      ?debug("~p: init(~p)~n", [?MODULE, Opts]),
      Chal = rand_bytes(4),
      MyId = proplists:get_value(id, Opts, undefined),
      case proplists:get_value(keys, Opts) of
  