#data
interface A {
  async iterable < DOMString ?, long >;
};
#processed
{
  "A": ["interface", {
    "iterable": ["async_iterable", {
      "keys_type": ["nullable", "DOMString"],
      "values_type": "long"
    }],
    "members": {}
  }]
}

#data
interface A {
  async iterable < DOMString , long >;
};
#processed
{
  "A": ["interface", {
    "iterable": ["async_iterable", {
      "keys_type": "DOMString",
      "values_type": "long"
    }],
    "members": {}
  }]
}