If you're asking me, it depends on what gets filled in for "syntax". I see no
reason to explicitly prohibit classes from participating, though.
- Dave Sweeris
> On May 30, 2016, at 16:12, Vladimir.S <sva...@gmail.com> wrote:
>
> In case we discuss this feature not for just value types but for classes also
> - will such AutoEquatable allows to implement protocol manually?
>
> Now we can have:
>
> func == (lhs: A, rhs: A) -> Bool { return true }
> class A: Hashable { var hashValue: Int { return 100 } }
> class B: A { override var hashValue: Int { return 200 } }
>
> So, if we'll have
> class A: AutoHashable { }
> or
> class A: deriving Hashable { }
> will we be able to have:
> class B: A { override var hashValue: Int { return 200 } }
> ?
>
> (The same question was for `deriving` proposal)
> Please note that we probably don't want/have no rights to modify the
> definition of class A.
>
> There is no such question for auto-derived Hashable in case of simple
> conformance as we do now `class A: Hashable`.
>
>> On 30.05.2016 23:45, David Sweeris wrote:
>> What about declaring the requirements for auto-conformance in a sub-protocol?
>> @auto protocol AutoEquatable : Equatable {
>> //"syntax" for how to conform to Equatable
>> }
>>
>> struct Foo : AutoEquatable {} //the compiler automatically synthesizes
>> everything
>> struct Bar : Equatable {} //you manually conform
>>
>> It would be a compiler error to conform to an `@auto` protocol if the
>> compiler couldn't apply the provided "syntax" to the conforming type.
>>
>> (I have no clue what this "syntax" could be, other than some expansion of
>> generics and/or a macro system)
>>
>> Anyway, does that help? It satisfies both the "explicit conformance" crowd
>> and the "no new keywords" (at least at the "call" site) crowd.
>>
>> - Dave Sweeris
>>
>>> On May 30, 2016, at 15:26, Vladimir.S via swift-evolution
>>> <swift-evolution@swift.org> wrote:
>>>
>>> I see these two groups: both wants explicit conformance to protocols, but
>>> first thinks that current syntax is enough (`: Equatable`) and second
>>> thinks we should introduce new keyword `deriving` for this(`: deriving
>>> Equatable`). I see no opinions(except the one opinion in proposal itself)
>>> to automatically deriving without explicit decoration.
>>
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