anchor.diff:      RscCatId = p(Id, category_id, Context),
       m_category:is_a(RscCatId, Context).
   
  +%% @doc Return the categories and the inherited categories of the resource. Returns a list with category ids
  +%% @spec is_a(int(), Context) -> list()
  +is_a_id(Id, Context) ->
  +    RscCatId = p(Id, category_id, Context),
  +	[ RscCatId | m_category:get_path(RscCatId, Context)].
  +
   %% @doc Check if the resource is in a categorie.
   %% @spec is_a(int(), atom(), Context) -> bool()
   is_a(Id, Cat, Context) ->
  
positive.code: 	is_visible/2, is_editable/2, is_ingroup/2, is_me/2, 
  	is_cat/3,
  	is_a/2,
  	is_a/3,
  	
  	p/3,
  
negative.code:     m_rsc_update:insert(Props, Context).
  
  %% @doc Delete a resource
  %% @spec delete(Props, Context) -> ok | {error, Reason}
  delete(Id, Context) when is_integer(Id) ->
      m_rsc_update:delete(Id, Context).
  
  