Expression implicitly coerced from 'String?' to Any

swift string optional
Dewangga Arie Baskara picture Dewangga Arie Baskara · Nov 19, 2016 · Viewed 40.3k times · Source

I have some error like this "Expression implicitly coerced from String? to Any" this is my code :

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
    // Override point for customization after application launch.

    FIRApp.configure()
    FIRAuth.auth()?.signIn(withEmail: "[email protected]", password: "mypassword", completion: { (user, error) in
        if (error != nil) {
            print(user?.email)
        }else {
            print(error?.localizedDescription)
        }
    })

    return true
}

Error in this line 

print(user?.email)

And

print(error?.localizedDescription)

Please help me

Answer

Luca D'Alberti picture Luca D'Alberti · Nov 19, 2016

The print function requires a set of Any parameters. String is a Any. In this case Xcode is telling you that it implicitly coerced the optional string into an Any object (by transforming the String value in Optional(value)).

To avoid this warning, you can simply use a default value or unwrap the String?

print(user?.email ?? "User instance is nil")
print(user!.email)

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