userInfo = ["username":username]
userInfo = ["email":email]
userInfo = ["password":password]

userInfo!["username"] = username
userInfo!["email"] = email
userInfo!["password"] = password

userInfo = ["username":username]
userInfo!["email"] = email
userInfo!["password"] = password

nextPressed()
{
    if let userInfo:[String:String] = try registrationValidation()
    {
        print("(userInfo)")
    }
}

func registrationValidation () throws -> [String:String]?
{
    var userInfo: [String:String]?
    var problems: [ValidationMessage] = []

    if let username = usernameField.text
    {
        let p1 = validateUsername(username)
        problems.appendContentsOf(p1)
        userInfo = ["username":username]

        //userInfo!["username"] = username
        //Above results in nil, yet lines below work?
    }

    if let email = emailField.text
    {
        let p2 = validateEmail(email)
        problems.appendContentsOf(p2)
        //userInfo = ["email":email]
        userInfo!["email"] = email
    }

    if let password = passwordField.text
    {
        let p3 = validatePassword(password)
        problems.appendContentsOf(p3)
        //userInfo = ["password":password]
        userInfo!["password"] = password
    }

    if !problems.isEmpty{
        throw ValidationError(problems:problems)
    }
    else
    {
        print("validation succeeded")
        return userInfo
    }
}