Good observation. Tcl's {a b} also represents something not possible in JSON: {["a"]: ["b"]} The string a can be treated as "a", ["a"], [["a"]],

Good observation. Tcl's {a b} also represents something not possible in JSON: {["a"]: ["b"]} The string a can be treated as "a", ["a"], [["a"]], [[["a"]]], ... by list operations.