anchor.diff:  
   -ifdef(EQC).
   
  +
   properties_test() ->
      ?assert(?MODULE:check()).
   
  
positive.code:        end).
  
  
  prop_query_inv() ->
     ?FORALL(InQ, dht_query(),
         begin
             OutQ = decode_msg(query_to_bencode(InQ)),
             OutQ =:= InQ
         end).
  
  -endif. %% EQC
  -endif. %% TEST
  
negative.code: 
  dht_query() ->
     All = [ping_query(), find_node_query(), get_peers_query(), announce_query()],
      oneof([{dht_query, Method, transaction(), lists:sort(Params)}
  	       || {Method, Params} <- All]).
  
  prop_inv_compact() ->
     ?FORALL(Input, list(dht_node()),
  