anchor.diff:      z_datamodel:manage(?MODULE, Datamodel, Context),
   
       %% Update some predicates so they can refer to category RDF, too
  -    case m_rsc:uri_lookup("http://xmlns.com/foaf/0.1/depiction", Context) of 
  +    case m_rsc:uri_lookup("http://xmlns.com/foaf/0.1/depiction", Context) of
           undefined -> noop;
           PredId ->
               Objects = m_predicate:objects(PredId, Context),
  
positive.code: 
  %% @doc When asked for properties of an RDF resource, ask the RDF data source to
  %%      provide extra properties
  observe_rsc_get(#rsc_get{id=_Id}, Props, Context) ->
  
      %% Only act on non-authoritative resources
  
negative.code:         false ->
              RscUri = proplists:get_value(uri, Props),
              case z_utils:is_empty(RscUri) of
                  true ->
                      Props;
                  false ->
                      z_notifier:foldl(#rdf_get{uri=RscUri}, Props, Context)
  