output.js

var Foo = function Foo() {
  "use strict";

  babelHelpers.classCallCheck(this, Foo);

  _prop.set(this, {
    writable: true,
    value: "foo"
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};

var _prop = new WeakMap();

var Bar =
/*#__PURE__*/
function (_Foo) {
  "use strict";

  babelHelpers.inherits(Bar, _Foo);

  var _super = babelHelpers.createSuper(Bar);

  function Bar(...args) {
    var _this;

    babelHelpers.classCallCheck(this, Bar);
    _this = _super.call(this, ...args);

    _prop2.set(babelHelpers.assertThisInitialized(_this), {
      writable: true,
      value: "bar"
    });

    return _this;
  }

  return Bar;
}(Foo);

var _prop2 = new WeakMap();