You can also get a heterogenous dictionary, but it needs a type erasing helper
box. With the following declarations:
public func ==<T: Equatable>(lhs: T, rhs: Any) -> Bool {
if let rhs = rhs as? T { return lhs == rhs } else { return false }
}
public struct AnyKey : Hashable {
public let hashValue: Int
public let key: Any
public let equals: (AnyKey) -> Bool
init<T: Hashable>(_ key: T) {
self.hashValue = key.hashValue
self.key = key
self.equals = { self.key as! T == $0.key }
}
}
public func == (lhs: AnyKey, rhs: AnyKey) -> Bool { lhs.equals(rhs) }
You can now create a heterogenous [AnyKey: Any] dictionary. Note that `AnyKey`
is not very memory efficient.
> On Mar 25, 2016, at 5:27 PM, Hooman Mehr <[email protected]> wrote:
>
>
>> On Mar 25, 2016, at 2:51 PM, Jason Sadler via swift-users
>> <[email protected] <mailto:[email protected]>> wrote:
>>
>> (My particular use case can be seen here:
>> https://gist.github.com/sadlerjw/2cc16b4375b02fe7f400
>> <https://gist.github.com/sadlerjw/2cc16b4375b02fe7f400> … and the best
>> information I’ve been able to find on this so far is here:
>> http://stackoverflow.com/questions/33112559/protocol-doesnt-conform-to-itself/33524927#33524927
>>
>> <http://stackoverflow.com/questions/33112559/protocol-doesnt-conform-to-itself/33524927#33524927>)
>
> Here is the best you can do for your particular use case:
>
> protocol AnyEquatable { func equals(other: Any) -> Bool }
>
> func ==<T: Equatable>(lhs: T, rhs: Any) -> Bool {
>
> if let rhs = rhs as? T { return lhs == rhs } else { return false }
> }
>
> extension Bool: AnyEquatable { func equals(other: Any) -> Bool { return
> self == other } }
>
> extension Int: AnyEquatable { func equals(other: Any) -> Bool { return
> self == other } }
>
> extension Double: AnyEquatable { func equals(other: Any) -> Bool { return
> self == other } }
>
> extension String: AnyEquatable { func equals(other: Any) -> Bool { return
> self == other } }
>
> extension Array {
>
> func indexOfAny(element : AnyEquatable) -> Index? { return indexOf {
> element.equals($0) } }
> }
>
> var array: [Any] = [false, 1, 2.0, "three"]
>
> array.indexOfAny(2.0)
>
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