[swift-evolution] Custom Covariance/Contravariance

Peter Livesey pdlivesey at gmail.com
Fri May 20 13:34:32 CDT 2016

I'm working on a proposal for adding covariance and contravariance to
custom classes. For instance:

let a = MyBag<Dog>()
let b: MyBag<Animal> = a

I cannot find any threads which have discussed this yet, but maybe I'm
missing something. Has this been discussed?

If not, I'll continue with my proposal and have something more soon.

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