[swift-evolution] Enhanced existential types proposal discussion
austinzheng at gmail.com
Thu May 26 10:36:49 CDT 2016
Yes, that's definitely an oversight.
That being said, the example is also actually incorrect, because AFAIK it's not possible to conform a type T to multiple protocols A and B, and have A.Element and B.Element be different types (i.e. the constraint is redundant). So it should be rewritten as well.
> On May 26, 2016, at 8:00 AM, Matthew Johnson via swift-evolution <swift-evolution at swift.org> wrote:
>> On May 26, 2016, at 9:54 AM, Jan E. Schotsman via swift-evolution <swift-evolution at swift.org> wrote:
>> In the "where clause" section, shouldn't this be allowed:
>> let a : Any<Collection, SetAlgebraType where Collection.Element == SetAlgebraType.Element>
>> I am asking because the acceptable type equality constraint is stated as:
>> Type equality constraint: X == ConcreteType
> Yes, you should definitely be able to equate two associate types! If the proposal isn’t clear about that it is probably just an oversight. Good catch!
>> Jan E.
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