text: function _checkPrivateRedeclaration(obj, privateCollection) {
      if (privateCollection.has(obj)) {
          throw new TypeError("Cannot initialize the same private elements twice on an object");
      }
  }
  function _classPrivateFieldInit(obj, privateMap, value) {
      _checkPrivateRedeclaration(obj, privateMap);
      privateMap.set(obj, value);
  }
  // @target: es2015
  class B {
  }
  class A extends B {
      constructor(){
          void 0;
          super();
          _classPrivateFieldInit(this, _x, {
              writable: true,
              value: void 0
          });
      }
  }
  var _x = new WeakMap();
  