ios - 错误 "Constant ' self.apiKey' used before being initialized"in Initializer

Question

我有一个 YoutubeAPIClient 类:

import Foundation

class YoutubeAPIClient {
    let apiKey: String?

    init?() {
        do {
            apiKey = try Environment().getValue(for: "YOUTUBE_API_KEY") as? String
        } catch {
            //TODO: Implement error handling
            print(error)
        }
    }
}

在 init 方法中我试图初始化 apiKey 但它说:

Constant 'self.apiKey' used before being initialized

如果有帮助，我已经包含了环境代码结构:

import Foundation

struct Environment {

    func getValue(for key: String) throws -> Any {

        guard let value = ProcessInfo.processInfo.environment[key] else {
            throw GenericError.noValueForKeyInEnvironment
        }

        return value
    }
}

Answer 1

您必须处理错误，否则实例将以未定义状态结束(apiKey 在发生错误时未初始化)。

由于您的init 已经是可失败的，您可以只返回nil:

} catch {
    print(error)
    return nil
}