{
  "@context": {
    "ex": "http://example.com/",
    "foo": {"@id": "http://example.com/foo", "@container": "@list"}
  },
  "@graph": [
    {"@id": "_:b0", "foo": ["bar"]},
    {"@id": "_:b1", "ex:foo": "foo"},
    {"@id": "_:b2", "ex:bar": "bar"}
  ]
}