{
    "type": "object",
    "properties": {
        "foo": {
            "$ref": "#/definitions/Enum"
        }
    },
    "required": [
        "foo"
    ],
    "definitions": {
        "Enum": {
            "type": [
                "number",
                "boolean",
                "string",
                "null"
            ],
            "enum": [
                0,
                1,
                null,
                "str",
                true
            ]
        }
    },
    "$schema": "http://json-schema.org/draft-04/schema#"
}