{
  "@context": {
    "@vocab": "http://example/",
    "id": "@id",
    "type": "@type",
    "Foo": {"@context": {"id": null, "type": null}}
  },
  "id": "http://example.org/id",
  "type": "http://example/type",
  "a": {
    "@id": "http://example.org/Foo",
    "@type": "Foo",
    "bar": {"@id": "http://example.org/baz"}
  }
}