> On Sep 28, 2016, at 9:27 AM, Robert Widmann via swift-evolution
> <swift-evolution@swift.org> wrote:
>
> To make this kind of pattern type safe you would, for example, need to keep
> track metatype pointers too and use the dynamic cast machinery to check the
> type on retrieval.
Actually, a somewhat different (DispatchSpecificKey-style) design makes type
safety pretty easy:
import Cocoa
let myValue = AssociatedValue(.strong, ofType: String.self, on:
NSView.self)
let view = NSView()
myValue[view] = "Hello, world!"
myValue[view]
Implementation here:
<https://gist.github.com/brentdax/75bfd619379fea53d8ca8afaa16d95bb>
Nevertheless, I don't think this should be shipped in Swift; associated objects
are as esoteric as they come.
--
Brent Royal-Gordon
Architechies
_______________________________________________
swift-evolution mailing list
swift-evolution@swift.org
https://lists.swift.org/mailman/listinfo/swift-evolution
