Ios SWIFT中具有可选返回类型和泛型的网络请求

向服务器发出请求时，有时需要数据作为结果(例如GET)，有时则不需要(例如PUT).在我的例子中，我有一个WebSocket连接，它用于告诉服务器事情(不返回数据)，但也用于请求数据(返回的数据).

我已经为服务器定义了一个带有不同类型的请求(事件)的枚举:

public enum OutgoingEvent: String, Codable {
    case user
    case identification
    // ... more events
    
    var objectType: Codable.Type? {
        switch(self) {
        case .user:
            User.self
        // ... more cases
        default:
            nil
        }
    }
}

objectType表示预期作为请求结果的对象类型(用于解码接收到的JSON).对于一些事件，这是一些可解码的，对于其他事件，这是空的(没有预期的数据作为返回).

How do I write a function that I can call for all kinds of events, and get as a return either the kind of object specified by 100, or nothing at all (depending on the event)?此外，由于socketIO库的缘故，我需要从基于回调的函数调用转换为Async/AWait语法(但这本身与泛型部分不同).

我试过这个:

func sendWithAck<T: Codable>(event: OutgoingEvent, data: [[String : Any]], completion: @escaping (Result<T?, Error>) -> ()) throws {
            // getting data from socket ...
            guard let resultType = event.objectType else {
                completion(.success(nil))
                return
            }
            
            guard let decodedObject = try? self.decodeFromDict(object: result, type: resultType) as? T else {
                completion(.failure(ServerCommunicationError.invalidDataFromServer("Could not decode result data.")))
                return
            }
            
            completion(.success(decodedObject))
}

func sendWithAck<T: Codable>(event: OutgoingEvent, data: [[String : Any]]) async throws -> T? {
        return try await withCheckedThrowingContinuation { continuation in
            do {
                try sendWithAck(event: event, data: data) { (result: Result<T?, ServerCommunicationError>) in
                    continuation.resume(with: result)
                }
            } catch(let error) {
                continuation.resume(throwing: error)
            }
        }
    }

但当你打电话的时候:

let User : User = try await ServerService.shared.sendWithAck(event: event, data: [updateData])

我得到"Generic parameter 'T' could not be inferred"和"Cannot convert value of type 'T?' to specified type 'User'"