text: function _classCallCheck(instance, Constructor) {
      if (!(instance instanceof Constructor)) throw new TypeError("Cannot call a class as a function");
  }
  function _getPrototypeOf(o) {
      return _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf : function _getPrototypeOf(o) {
          return o.__proto__ || Object.getPrototypeOf(o);
      }, _getPrototypeOf(o);
  }
  function _setPrototypeOf(o, p) {
      return _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) {
          return o.__proto__ = p, o;
      }, _setPrototypeOf(o, p);
  }
  var Base = function() {
      "use strict";
      _classCallCheck(this, Base);
  }, C = function(Base) {
      "use strict";
      function C() {
          var self, call, obj;
          return _classCallCheck(this, C), self = this, (call = _getPrototypeOf(C).call(this)) && ("object" == ((obj = call) && "undefined" != typeof Symbol && obj.constructor === Symbol ? "symbol" : typeof obj) || "function" == typeof call) ? call : (function(self) {
              if (void 0 === self) throw new ReferenceError("this hasn't been initialised - super() hasn't been called");
              return self;
          })(self);
      }
      return !function(subClass, superClass) {
          if ("function" != typeof superClass && null !== superClass) throw new TypeError("Super expression must either be null or a function");
          subClass.prototype = Object.create(superClass && superClass.prototype, {
              constructor: {
                  value: subClass,
                  writable: !0,
                  configurable: !0
              }
          }), superClass && _setPrototypeOf(subClass, superClass);
      }(C, Base), C;
  }(Base);
  