swift3 - Swift 2.3 到 Swift 3.0 对成员 'joined' 出现模糊引用错误

Question

我正在努力将 swift 2.3 转换为 swift 3.0；

Swift 2.3 代码:

extension ContextDidSaveNotification: CustomDebugStringConvertible {
    public var debugDescription: String {
        var components = [notification.name]
        components.append(managedObjectContext.description)
        for (name, set) in [("inserted", insertedObjects), ("updated", updatedObjects), ("deleted", deletedObjects)] {
            let all = set.map { $0.objectID.description }.joinWithSeparator(", ")
            components.append("\(name): {\(all)}")
        }
        return components.joinWithSeparator(" ")
    }
}

Swift 3.0 代码:

extension ContextDidSaveNotification: CustomDebugStringConvertible {
    public var debugDescription: String {
        var components = [notification.name]
        components.append(Notification.Name(rawValue: managedObjectContext.description))
        for (name, set) in [("inserted", insertedObjects), ("updated", updatedObjects), ("deleted", deletedObjects)] {
            let all = set.map { $0.objectID.description }.joined(separator: ", ")
            components.append(Notification.Name(rawValue: "\(name): {\(all)}"))
        }
        return components.joined(separator: " ")
    }
}

但我收到错误:对 Swift 3.0 代码中的激光返回的 memeber 'joined()' 的引用不明确。

如何解决这个问题？我做了很多研究，但找不到有效的解决方案。

谢谢

Answer 1

joined(separator:)声明为 Array<String> ，不是Array<Notification.Name> :

// somewhere in standard library
extension Array where Element == String {

    public func joined(separator: String = default) -> String
}

正如@vadian 指出的，Notification.Name不等于String ，所以你需要先转换你的数组。这应该有效:

components
  .map({ $0.rawValue })
  .joined(separator: " ")