anchor.diff:           iq/5,
   
            publish/3, publish/4, publish/5,
  +         publish_with_options/4, publish_with_options/5, publish_with_options/6,
  +
            retract/4,
            get_items/4,
            get_all_items/3,
  
positive.code:            attrs = [{<<"node">>, NodeName}],
             children = skip_undefined([Item])}.
  
  items_element(NodeName) ->
      #xmlel{name = <<"items">>,
             attrs = [{<<"node">>, NodeName}]}.
  
negative.code: 
  -type pubsub_node_id() :: {pep | binary(), binary()}.
  -export_type([pubsub_node_id/0]).
  
  -type publish_options() :: [{binary(), binary()}].
  
  -type form_field() :: {Var :: binary(), Value :: binary()}
                        | {Var :: binary(), Type :: binary(), Value :: binary()}.
  