Hey Joe,

I’m +1 on the overall direction, but I have some questions/concerns about the 
"Ambivalent dynamic casting from Any” section.

1) When you suggest that `x as String` succeeds but `x as NSString` fails, I 
assume this would only be true *after* SE-0083, since otherwise we’d be 
violating transitivity of `as` casts?

2) Have you considered the only allowing `as` casts to the bridged type (e.g. 
String) for values coming from `id` at the language level, but providing some 
guaranteed optimization that if you immediately convert to the ObjC class type 
(ie. NSString(x as! String)) we give zero-cost round-tripping? Would that be 
detectable?  I think making `value as? NSFoo` fail or succeed depending on 
whether the value came from ObjC  will be a source of subtle bugs.  What if I 
have multiple sources of values - some from ObjC, some from Swift - and stuff 
them into an [Any].

Ben

> On Jul 5, 2016, at 8:45 AM, Chris Lattner via swift-evolution 
> <[email protected]> wrote:
> 
> Hello Swift community,
> 
> The review of "SE-0116: Import Objective-C id as Swift Any type" begins now 
> and runs through July 11. The proposal is available here:
> 
>       
> https://github.com/apple/swift-evolution/blob/master/proposals/0116-id-as-any.md
> 
> Reviews are an important part of the Swift evolution process. All reviews 
> should be sent to the swift-evolution mailing list at
> 
>       https://lists.swift.org/mailman/listinfo/swift-evolution
> 
> or, if you would like to keep your feedback private, directly to the review 
> manager.
> 
> What goes into a review?
> 
> The goal of the review process is to improve the proposal under review 
> through constructive criticism and contribute to the direction of Swift. When 
> writing your review, here are some questions you might want to answer in your 
> review:
> 
>       * What is your evaluation of the proposal?
>       * Is the problem being addressed significant enough to warrant a change 
> to Swift?
>       * Does this proposal fit well with the feel and direction of Swift?
>       * If you have used other languages or libraries with a similar feature, 
> how do you feel that this proposal compares to those?
>       * How much effort did you put into your review? A glance, a quick 
> reading, or an in-depth study?
> 
> More information about the Swift evolution process is available at
> 
>       https://github.com/apple/swift-evolution/blob/master/process.md
> 
> Thank you,
> 
> -Chris Lattner
> Review Manager
> 
> 
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