             let nested: [String:Any] = try result <| "nested"
 
             XCTAssertEqual(string, "A String")
+            XCTAssertEqual(truth, true)
+            XCTAssertNil(missing)
             XCTAssertEqual(small, 2)
             XCTAssertEqual(medium, 66_000)
             XCTAssertEqual(large, 4_200_000_000)

    func testMarshalingSwiftValues() {
        let object: MarshalDictionary = [
            "string": "A String",
            "small": 2,
            "medium": 66_000,
            "large": 4_200_000_000,

            let data = try JSONSerialization.data(withJSONObject: object, options: [])
            let result = try JSONParser.JSONObjectWithData(data)
            let string: String = try result <| "string"
            let truth: Bool = try result <| "truth"
            let missing: String? = try result <| "missing"
            let small: Int = try result <| "small"
            let medium: Int = try result <| "medium"
            let large: Int = try result <| "large"
