Swift枚举：普通/非可用的初始化程序不支持 - 或只是破碎？

问题描述

限时删除！！

我已阅读有关Swift的但没有看到任何明确的正常，不可用的品种。我有没有想过的东西，或者是常规的初始化器不支持具有原始值的枚举器，即使没有可能的初始化程序可能会失败（由于初始化程序违反默认值）：

{pre> enum FailableSeason：Int {

init？（d：Int）{

switch（d％365）{
case 60 ... 151：
self = .Spring
case 152 ... 243：
self = .Summer
case 244 ... 334：
self = .Fall

//默认提供，保证有效
默认值：
self = .Winter
}
}

case Spring
case Summer
case秋天
case冬天
}

枚举ImplicitlyUnwrappedFailableSeason：Int {

init！（d：Int）{

switch（d％365）{
case 60 ... 151：
self = .Spring
case 152。 .243：
self = .Summ呃
case 244 ... 334：
self = .Fall

//默认提供，保证有效
默认值：
self =。冬天
}
}

案例春季
案例夏季
案件秋季
案件冬季
}

enum NonFailableSeason：Int {

init（d：Int）{

switch（d％365）{
case 60 ... 151：
self = .Spring
case 152 ... 243：
self = .Summer
case 244 ... 334：
self = .Fall

//默认提供，保证有效
默认值：
self = .Winter
}
}

case Spring
case夏天
case秋天
case冬天
}


让thisWorks = FailableSeason（d：60）
let thisFails = ImplicitlyUnwrappedFailableSeason（d： 60）
let andThisFails = NonFailableSeason（d：0）


请注意，我将它分成单独的枚举，以确保它不是冲突的初始化器的问题

解决方案

以前用于Swift 1.1（Xcode 6.1.1）但在Swift 1.2（Xcode 6.3）中失败。
这是一个在Apple开发人员论坛上讨论的错误： Swift 1.2 - 初始化枚举

该讨论中给出了两种解决方法：使用模块/应用程序名称
作为前缀：

  let workaround1 = NameOfYourModule.NonFailableSeason（d：0）
  

或者显式调用init方法：

  let workaround2 = NonFailableSeason.init（d：0）
  

更新：这在Xcode 6.3 beta 2（6D532l）版本中已经修复。

I have read documentation on Swift's failable initializer's but didn't see anything explicit about the normal, non-failable variety. Did I miss something, or are regular initializer not supported for enumerators with raw values, even when there is no possibility that the initializer could fail (since the initializer defers to a default value):

enum FailableSeason : Int {

    init?(d: Int) {

        switch (d % 365) {
        case 60...151:
            self = .Spring
        case 152...243:
            self = .Summer
        case 244...334:
            self = .Fall

        // default provided, guaranteed to be valid
        default:
            self = .Winter
        }
    }

    case Spring
    case Summer
    case Fall
    case Winter
}

enum ImplicitlyUnwrappedFailableSeason : Int {

    init!(d: Int) {

        switch (d % 365) {
        case 60...151:
            self = .Spring
        case 152...243:
            self = .Summer
        case 244...334:
            self = .Fall

            // default provided, guaranteed to be valid
        default:
            self = .Winter
        }
    }

    case Spring
    case Summer
    case Fall
    case Winter
}

enum NonFailableSeason : Int {

    init(d: Int) {

        switch (d % 365) {
        case 60...151:
            self = .Spring
        case 152...243:
            self = .Summer
        case 244...334:
            self = .Fall

            // default provided, guaranteed to be valid
        default:
            self = .Winter
        }
    }

    case Spring
    case Summer
    case Fall
    case Winter
}


let thisWorks = FailableSeason(d: 60)
let thisFails = ImplicitlyUnwrappedFailableSeason(d: 60)
let andThisFails = NonFailableSeason(d: 0)

Note that I broke this into separate enums to make sure that it wasn't a problem of conflicting initializers.

解决方案

This used to work with Swift 1.1 (Xcode 6.1.1) but fails in Swift 1.2 (Xcode 6.3).It is a bug which has been discussed in the Apple Developer Forum: Swift 1.2 - Initializing Enums.

Two workarounds are given in that discussion: Use the module/app nameas a prefix:

let workaround1 = NameOfYourModule.NonFailableSeason(d: 0)

Or call the init method explicitly:

let workaround2 = NonFailableSeason.init(d: 0)

Update: This has been fixed in the Xcode 6.3 beta 2 (6D532l) release.

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