Switch statement for imported NS_OPTIONS (RawOptionSetType) in Swift?

Question

The switch statement in Swift is so much more expressive. I\'m wondering if this might be possible:

Lets look at UIViewAutoresizing for example. It\'s defined in Objecti

Answer 1

I was frustrated enough about this problem that I wrote a Bitmask class that can handle these use cases. The code is up on Github: brynbellomy/SwiftBitmask

It allows you to do stuff like this with any kind of object as your underlying type (here I'm using an enum):

enum MonsterAttributes : IBitmaskRepresentable, IAutoBitmaskable {
    case Big, Ugly, Scary

    static var autoBitmaskValues : [MonsterAttributes] = [.Big, .Ugly, .Scary,]
    var  bitmaskValue: UInt16  { return AutoBitmask..autoBitmaskValueFor(self) }
    init(bitmaskValue: UInt16) { self = AutoBitmask.autoValueFromBitmask(bitmaskValue) }
}

// various ways to initialize
let option : MonsterAttributes = .Ugly

let bitmaskOfOption        = Bitmask(option)
let anotherBitmaskOfOption = |MonsterAttributes.Ugly // same as bitmaskOfOption

let orWithVar = option | .Big                 // == Bitmask with a bitmaskValue of 1 | 2
let simpleOr  = MonsterAttributes.Big | .Ugly // == Bitmask with a bitmaskValue of 1 | 2

// getting the raw integral bitmask value
let simpleOrValue = simpleOr.bitmaskValue                        // == UInt16(1 | 2)
let orValue       = (MonsterAttributes.Big | .Ugly).bitmaskValue // == UInt16(1 | 2)

// implements BooleanType
if simpleOr & .Ugly             { /* this code will execute */ }

// supports pattern matching operator
if simpleOr ~= .Ugly            { /* this code will execute */ }
if simpleOr ~= (.Ugly | .Scary) { /* this code will execute */ }

... and all you have to do is implement a one-property protocol.

I'm really curious if anyone has any feedback on or ideas for the code, so please leave an issue in the queue if you think of anything!