anchor.diff:          fun(Id, Acc) ->
               {ok, Value1} = do_get(Eredis, Prefix, Id),
               Value = decode(Value1),
  -            Function({Id, Value}, Acc)
  +            Function({Id, decode(Value)}, Acc)
           end,
           Acc0,
           Objects
  
positive.code:         fun(Id, Acc) ->
              {ok, Value1} = do_get(Eredis, Prefix, Id),
              Value = decode(Value1),
              {NewValue, InnerResult} = Function({Id, Value}),
              case do_put(Eredis, Prefix, Id, NewValue) of
                  ok ->
                      Acc ++ [InnerResult]
  
negative.code: handle_call({update, Id, Function}, _From, #state{eredis=Eredis, prefix=Prefix}=State) ->
      Result = case do_get(Eredis, Prefix, Id) of
          {ok, Value} ->
              {NewValue, InnerResult} = Function({Id, decode(Value)}),
              case do_put(Eredis, Prefix, Id, NewValue) of
                  ok ->
                      InnerResult
  