         let success = json["success"].bool
         switch success {
         case .Success(let s):
-            XCTAssertTrue(s.value == true, "There should be `success`.")
-        case .Failure(let error):
-            XCTAssert(false, "There should be no error: \(error)")
+            XCTAssertTrue(s.value, "There should be `success`.")
+        case .Failure(let error):
+            XCTFail("There should be no error: \(error)")
         }
     }
     

                let per = Person.createWithJSON(person)
                switch per {
                case .Success(let p):
                    XCTAssertTrue(p.value.name != "", "People should have names.")
                case .Failure(let error):
                    XCTAssert(false, "There should be no `error`.")
                }
            }
        case .Failure(let error):
            XCTAssert(false, "There should be no error.")
        }
    }
    

                XCTAssertNotNil(z.int, "The `Int` should not be `nil`.")
            }
        case .Failure(let error):
            XCTFail("There should be no `error`.")
        }
    }

