var _obj, _ref; // @target: esnext, es2020, es2015 var count = 0; var obj = { }; function incr() { return ++count; } var oobj = { obj: obj }; var ref; (ref = (_obj = obj)[incr()]) !== null && ref !== void 0 ? ref : _obj[incr()] = incr(); var ref1; (ref1 = (_ref = oobj["obj"])[incr()]) !== null && ref1 !== void 0 ? ref1 : _ref[incr()] = incr();