struct CreateUser {
    let email: String
    let password: String
    func isValid() -> Bool {
        return email != "" && password != ""
    }

    func emailValid() -> Bool {
        let emailRegEx = "^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$"

        let emailTest = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
        return emailTest.evaluateWithObject(email)
    }
}

protocol CreateUserDelegate {
    func CreateUser(didSucceed user: CreateUser)
    func CreateUser(didError errorMessage: String)
}

func create(delegate: CreateUserDelegate) {
    switch self {
    case let CreateUser where user.isValid() && user.emailValid():
        //createuser

        break

    default:
        print("not mutch anything")
    }
}