var duplicate = { "key": "value", // $ Alert - duplicated on line 5 " key": "value", "1": "value", // $ Alert - duplicated on line 11 "key": "value", // $ Alert - duplicated on next line 'key': "value", // $ Alert - duplicated on next line key: "value", // $ Alert - duplicated on next line \u006bey: "value", // $ Alert - duplicated on next line "\u006bey": "value", // $ Alert - duplicated on next line "\x6bey": "value", 1: "value" }; var accessors = { get x() { return 23; }, set x(v) { } }; var clobbering = { x: 23, y: "hello", x: 42, x: 56, "y": "world" }