Xcode 8 swift 3中预期声明的无限循环

Question

这是代码。在最后的结束括号中我得到：

预期“，”宣言

它是无限的。你把它，然后错误是你必须删除。怎么了？我试过多次关闭和打开Xcode。

{

@IBOutlet weak var usernameTextField: UITextField!
@IBOutlet weak var passwordTextField: UITextField!

override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

@IBAction func createAccountTapped(_ sender: AnyObject) {

    let username = usernameTextField.text
    let password = passwordTextField.text

    Auth.auth().createUser(withEmail: username!, password: password!, completion: { (user, error) in
        if error != nil{
            let errorMessage = error?.localizedDescription

            // error creating account
            let alert = UIAlertController(title: "Error" , message: errorMessage, preferredStyle: .alert)
            alert.addAction(UIAlertAction(title: "Ok", style: .default, handler: nil))
            self.present( alert, animated: true, completion: nil)
        } else {

        // success
            if ((Error.self != nil)) {
            let alert = UIAlertController(title: "Nice!", message: "Ok, now that you have an account, let's go to the Log In screen", preferredStyle: .alert)
        let action = UIAlertAction(title: "OK", style: .default) { (action) -> Void in
            let ViewController = self.storyboard?.instantiateViewController(withIdentifier: "LoginVC")
            self.present(ViewController!, animated: true, completion: nil)
            }

            }
        }
}

一开始还有其他东西，但Stack Overflow不接受那么多代码。

Answer 1

Auth.auth().createUser(....)上没有右括号

只是为了确定术语：这是一个右括号)，这是一个结束括号}。你可能有太多的后者。