docs: protected boolean isGetterOrSetter(String name, int index, boolean setter) {
          Slot slot = slotMap.query(name, index);
          if (slot instanceof GetterSlot) {
              if (setter && ((GetterSlot)slot).setter != null) return true;
              if (!setter && ((GetterSlot)slot).getter != null) return true;
          }
          return false;
      }