[swift-evolution] [swift-evolution-announce] [Review] SE-0156: Class and Subtype existentials
david at hartbit.com
Wed Mar 1 14:16:20 CST 2017
> On 1 Mar 2017, at 21:01, Matthew Johnson via swift-evolution <swift-evolution at swift.org> wrote:
>> On Mar 1, 2017, at 1:59 PM, Brent Royal-Gordon via swift-evolution <swift-evolution at swift.org> wrote:
>> A good and necessary enhancement. My only objection is to the ordering rules—I'm not convinced that they pull their weight, especially given that typealiases can be used to introduce class constraints that aren't in the leftmost position. It's a lot of rules and strictures for a dubious benefit.
> I made a similar comment in the discussion thread. I don’t feel strongly enough to argue over it, but it does feel like a rather arbitrary limitation.
Same reasoning for class being the first in the inheritance/conformance list: it allows you to quickly read a list and see if there is a class where you expect it. The fact that one may come from a typealias is a different story: it's the difference between being able to quickly read an expression and understanding the whole function it's contained in.
>> Brent Royal-Gordon
>> Sent from my iPhone
>>> On Feb 28, 2017, at 1:11 PM, Douglas Gregor <dgregor at apple.com> wrote:
>>> Hello Swift community,
>>> The review of SE-0156 "Class and Subtype existentials" begins now and runs through March 7, 2017. The proposal is available here:
>>> Reviews are an important part of the Swift evolution process. All reviews should be sent to the swift-evolution mailing list at
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