[swift-evolution] Proposal: label-only constructors

[David Owens II]

Agreed. It's also likely that you'll be setting some internal flag with this information already. 

Sent from my iPhone

> On Dec 13, 2015, at 8:55 AM, Harlan Haskins via swift-evolution <swift-evolution at swift.org> wrote:
> 
> Also I think it’d be cleaner to just accept an enum in one initializer
> 
> enum KeyType {
>     case RSA
>     case Curve25519
>     case AES
> }
> 
> Then you get that semantic niceness of:
> 
> init(keyType: .RSA)
> init(keyType: .Curve25519)
> init(keyType: .AES)
> 
> — Harlan
> 
>> On Dec 13, 2015, at 11:41 AM, Sean Heber via swift-evolution <swift-evolution at swift.org> wrote:
>> 
>> In this particular example, perhaps Key should be an enum instead of a struct.
>> 
>> l8r
>> Sean
>> 
>> Sent from my iPad
>> 
>>> On Dec 13, 2015, at 10:07 AM, ilya via swift-evolution <swift-evolution at swift.org> wrote:
>>> 
>>> Good point on that. I still think the best solution is to take the existing syntax of
>>> 
>>> 
>>> struct Key {
>>>     init(forRSA:Void) { /* */ }
>>>     init(forCurve25519:Void) { /* */ }
>>>     init(forAES:Void) { /* */ }
>>> }
>>> 
>>> let a = Key(forRSA: ())
>>> 
>>> or 
>>> 
>>> let empty: Void = ()
>>> let c = Key(forAES: empty)
>>> 
>>> and make it somewhat easier to read.  Perhaps
>>> 
>>> let b = Key(forCurve25519: _ )
>>> 
>>> I think many people will read Key(forAES) as Key.init(_: forAES), so that may be not the best expression here.
>>> 
>>> 
>>> 
>>>> On Sun, Dec 13, 2015 at 4:21 PM, Drew Crawford <drew at sealedabstract.com> wrote:
>>>> 
>>>>> On Dec 13, 2015, at 7:13 AM, ilya <ilya.nikokoshev at gmail.com> wrote:
>>>>> 
>>>>> You can easily call a private parametrized init from a class function though. 
>>>> 
>>>> 
>>>> Sure, but we're just shuffling the deck.  We've gone from a bad public API to a bad private API.
>>>> 
>>>> Actually, it's worse, because we now have BOTH a bad private API AND a bad public API.  There is a reason that NSData.dataWithData(...) is a Swift compile error.
>>>> 
>>>> The (ab)use of class functions as constructors is a holdover from ObjC times.  If you want to make an instance in Swift, you should type ClassName( and see what autocomplete suggests; you should not have to read through the documentation of class functions to see if they are secretly constructors that have been filed at the wrong shelf in the library.
>>> 
>>> _______________________________________________
>>> swift-evolution mailing list
>>> swift-evolution at swift.org
>>> https://lists.swift.org/mailman/listinfo/swift-evolution
>>  _______________________________________________
>> swift-evolution mailing list
>> swift-evolution at swift.org
>> https://lists.swift.org/mailman/listinfo/swift-evolution
> 
> 
> _______________________________________________
> swift-evolution mailing list
> swift-evolution at swift.org
> https://lists.swift.org/mailman/listinfo/swift-evolution
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-evolution/attachments/20151213/9a0a833d/attachment.html>