{
  "identifier keys": { plain: 1, _dollar$2: 2 },

  "keys needing quotes": { "my-key": 3, "9x": 4, "": 5 },

  "keys starting with a slash": {
    "/tagged": 6,
    "//doubled": 7,
    "/circle": 8,
    "/uniqueSymbol": 9,
    "/Error@1": 10,
  },

  "unsafe key": { constructor: 11 },
}

--

identifier keys:
{plain:1,_dollar$2:2}
{
  plain: 1,
  _dollar$2: 2
}
{
  plain: 1,
  _dollar$2: 2
}

keys needing quotes:
{"my-key":3,"9x":4,"":5}
{
  "my-key": 3,
  "9x": 4,
  "": 5
}
{
  "my-key": 3,
  "9x": 4,
  "": 5
}

keys starting with a slash:
{"/tagged":6,"//doubled":7,"/circle":8,"/uniqueSymbol":9,"/Error@1":10}
{
  "/tagged": 6,
  "//doubled": 7,
  "/circle": 8,
  "/uniqueSymbol": 9,
  "/Error@1": 10
}
{
  "//tagged": 6,
  "///doubled": 7,
  "//circle": 8,
  "//uniqueSymbol": 9,
  "//Error@1": 10
}

unsafe key:
{constructor:11}
{
  constructor: 11
}
{
  "/constructor": 11
}