Swift 查找与OptionSet值关联的名称

所以我有一个

选项

：

struct Ability: OptionSet {
    let rawValue: Int

    static let create  = Ability(rawValue: 1 << 0)
    static let read    = Ability(rawValue: 1 << 1)
    static let update  = Ability(rawValue: 1 << 2)
    static let delete  = Ability(rawValue: 1 << 3)

    init(rawValue: Int) {
        self.rawValue = rawValue
    }
}

其中

convertoptionString（Ability.read）

将返回

“read”

当然我知道，

OptionSet

s也可以保存多个值，但我已经知道如何处理这种情况，所以这不是我需要帮助的问题

---

我希望这个问题可以通过某种聪明的思考来解决，但我还没有找到解决方法。有人想试一试吗？

更新您的

struct

以符合

CustomStringConvertible

并实现

description

属性：

struct Ability: OptionSet, CustomStringConvertible {
    let rawValue: Int

    static let create  = Ability(rawValue: 1 << 0)
    static let read    = Ability(rawValue: 1 << 1)
    static let update  = Ability(rawValue: 1 << 2)
    static let delete  = Ability(rawValue: 1 << 3)

    init(rawValue: Int) {
        self.rawValue = rawValue
    }

    var description: String {
        var vals = [String]()
        if self.contains(.create) {
            vals.append("create")
        }
        if self.contains(.read) {
            vals.append("read")
        }
        if self.contains(.update) {
            vals.append("update")
        }
        if self.contains(.delete) {
            vals.append("delete")
        }

        return vals.joined(separator: ",")
    }
}

print(Ability.read)
let opts: Ability = [ .read, .delete ]
print(opts)

struct-Ability:OptionSet，CustomStringConvertible{
让rawValue:Int
static let create=Ability（rawValue:1这很好。有没有办法只扩展
OptionSet
？@亲爱的，当然，你可以让
Ability
保持原样，然后创建
扩展Ability:CustomStringConvertible{
并将
description
放在扩展名中。我指的是
OptionSet
上的扩展名，而不是
Ability
@亲爱的，我不这么认为。从
OptionSet
无法知道给定的
OptionSet
的可能值列表及其对应的名称。这就是为什么我希望我们能做到这一点我不想强制我的代码的使用者去写一个描述变量，因为这样写太单调了。
struct Ability: OptionSet, CustomStringConvertible {
    let rawValue: Int

    static let create  = Ability(rawValue: 1 << 0)
    static let read    = Ability(rawValue: 1 << 1)
    static let update  = Ability(rawValue: 1 << 2)
    static let delete  = Ability(rawValue: 1 << 3)

    init(rawValue: Int) {
        self.rawValue = rawValue
    }

    var description: String {
        var vals = [String]()
        if self.contains(.create) {
            vals.append("create")
        }
        if self.contains(.read) {
            vals.append("read")
        }
        if self.contains(.update) {
            vals.append("update")
        }
        if self.contains(.delete) {
            vals.append("delete")
        }

        return vals.joined(separator: ",")
    }
}

print(Ability.read)
let opts: Ability = [ .read, .delete ]
print(opts)