anchor.diff:  delete(_, _, _) ->
     ok.
   
  -policy_changed(OldX = #exchange{name = Name}, NewX) ->
  +policy_changed(OldX, NewX) ->
     Bs = rabbit_binding:list_for_source(OldX),
     case gen_server:call(pgsql_listen, {delete, OldX, Bs}) of
       ok ->
  
positive.code: -module(pgsql_listen_exchange).
  
  -include("pgsql_listen.hrl").
  -include_lib("rabbit_common/include/rabbit.hrl").
  
  -behaviour(rabbit_exchange_type).
  
  
negative.code:   case gen_server:call(pgsql_listen, {validate, X}) of
      ok -> ok;
      {error, Reason} ->
        rabbit_log:error("postgresql connection validation failed: ~s", [Reason]),
        rabbit_misc:protocol_error(resource_error,
                                   "postgresql connection validation failed: ~s",
                                   [Reason])
    end.
  
  