docs: function (lib) {
      var res = _wlibs[lib];
      if (res == null) {
          res = Aria.getClassRef(lib);
          // TODO: check if res is a library
          _wlibs[lib] = res;
      }
      if (res === undefined) {
          this.$logError(this.WIDGET_LIBRARY_NOT_FOUND, [lib, this.tplClasspath]);
      }
      return res;
  }