output.js

var A =
/*#__PURE__*/
function () {
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  }

  babelHelpers.createClass(A, [{
    key: "foo",
    value: function foo() {
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}();

var B =
/*#__PURE__*/
function (_A) {
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    babelHelpers.classCallCheck(this, B);
    _this = _super.call(this, ...args);

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      value: babelHelpers.get(babelHelpers.getPrototypeOf(B.prototype), "foo", babelHelpers.assertThisInitialized(_this)).call(babelHelpers.assertThisInitialized(_this))
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    return _this;
  }

  return B;
}(A);

var _foo = new WeakMap();