struct ArgoUser: Argo.Decodable {
    
    let id: Int
    let name: String
    
    let birthdate: String?
    
    static func decode(json: JSON) -> Decoded<ArgoUser> {
        return curry(ArgoUser.init)
            <^> json <| "id"
            <*> json <| "name"
            <*> json <|? "birthdate"
    }
}

provider
    .request(.AllUsers) { result in
            
        if case let .Success(response) = result {
        
            do {
                let argoUsers:[ArgoUser] = try response.mapArrayWithRootKey("users")
                print("mapped to users: \(argoUsers)")
            } catch {
                print("Error mapping users: \(error)")
            }
        }
    }

provider
    .rx
    .request(.AllUsers)
    .mapArray(ArgoUser.self, rootKey: "users")
    .observeOn(MainScheduler.instance)
    .subscribeNext { users in
            
        self.users = users
        self.tableView.reloadData()
            
    }.addDisposableTo(disposeBag)

provider
    .reactive
    .request(.AllUsers)
    .mapArray(ArgoUser.self, rootKey: "users")
    .observeOn(UIScheduler())
    .start { event in

        switch event {
        case .Next(let users):
            self.users = users
            self.tableView.reloadData()
        case .Failed(let error):
            print("error: \(error)")
        default: break
        }
    }