gistfile1.swift

func loginUserWithUsername(username: String, password: String) throws -> String {
    guard username.characters.count != 0 else {
        throw LoginError.EmptyUsername
    }
    
    guard password.characters.count != 0 else {
        throw LoginError.EmptyPassword
    }
    
    ///Handle all the other,
    return "token:" + username
}