anchor.diff:  %% {messages, ppspp_messages()}
   %% ].
   
  --spec unpack(binary(), endpoint(), any()) -> {ok, datagram()}.
  -unpack(Datagram, _Peer, _State ) ->
  +-spec unpack(binary(), endpoint()) -> {ok, datagram()}.
  +unpack(Datagram, _Peer) ->
       {Channel, Maybe_Messages} = ppspp_channel:unpack_with_rest(Datagram),
       ?DEBUG("dgram: received on channel ~p~n",
              [ppspp_channel:channel_to_string(Channel)]),
  
positive.code: -endif.
  
  %% api
  -export([handle/2,
           handle/1,
           unpack/3,
           pack/1]).
  
  -opaque endpoint() :: {endpoint, list( endpoint_option())}.
  
negative.code: -export_type([endpoint/0,
                endpoint_option/0,
                datagram/0]).
  
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %% @doc translates raw udp packet into a tidy structure for later use
  