anchor.diff:           }).
   
   -define(AVS_FILE_EXT, ".avs").
  +-define(DEF_TIMEOUT, 30000).
   
   %%====================================================================
   %% API
  
positive.code: -spec(head(atom(), binary()) ->
               {ok, #metadata{}} | {error, any()}).
  head(Id, Key) ->
      gen_server:call(Id, {head, Key}).
  
  
  %% @doc Retrieve objects from the object-storage by Key and Function
  
negative.code: -spec(delete(atom(), #object{}) ->
               ok | {error, any()}).
  delete(Id, Object) ->
      gen_server:call(Id, {delete, Object}, ?DEF_TIMEOUT).
  
  
  %% @doc Retrieve an object's metadata from the object-storage
  