code: @Override
      public final boolean delete(Context cx, Object id) {
          if (cx == null) cx = Context.getCurrentContext();
          XMLName xmlName = lib.toXMLNameOrIndex(cx, id);
          if (xmlName == null) {
              long index = ScriptRuntime.lastUint32Result(cx);
              // XXX Fix this
              delete((int)index);
              return true;
          }
          deleteXMLProperty(xmlName);
          return true;
      }
docs: Implementation of ECMAScript [[Delete]].