> On Jun 16, 2017, at 8:44 AM, David Hart <[email protected]> wrote:
> 
> Okay, I undertand. I’m just worried that the proposal is a net negative if 
> the keywords stay optional. I’ll mention it in more detail once we get to the 
> review period.
> 
> Thanks for the work on the proposal!!


I believe a breaking change has little chance of being accepted at this point 
in the language lifecycle. Adding opt-in compiler auditing to increase safety 
is, IMO, a net positive. It's a deliberate trade-off. We have included other 
designs to allow the core team to choose an alternative they feel is best for 
the philosophy and direction of Swift. This doesn't close the door to future 
language releases enhancing the concept, phasing out the second keyword, or 
introducing keywords for additional safety auditing.

I find it a dangerous philosophy to insist that any new proposal be 
ideologically pure. Imperfect proposals can still improve the language within 
the realities of the timelines, user base, and code base of the Swift 
community.  

-- E

> 
>> On 16 Jun 2017, at 16:33, Erica Sadun <[email protected] 
>> <mailto:[email protected]>> wrote:
>> 
>> As we say in our introduction, we're pitching the most conservative 
>> approach. 
>> 
>> The proposal was designed for minimal language impact. It chooses a 
>> conservative approach that can be phased in first over time and language 
>> release over more succinct alternatives that would impact existing code 
>> bases.
>> 
>> We discuss the one keyword version (which most of us are a fan of) in the 
>> alternatives. The core team has to decide how much they're willing to allow 
>> existing code to warn and/or break, which is the consequence of the one 
>> keyword solution.
>> 
>> -- E
>> 
>>> On Jun 16, 2017, at 7:44 AM, David Hart <[email protected] 
>>> <mailto:[email protected]>> wrote:
>>> 
>>> Erica, any thoughts on only having default and making it an error in a 
>>> future version of Swift like was discussed on this thread? The idea seems 
>>> to have a few supporters.
>>> 
>>>> On 16 Jun 2017, at 15:33, Erica Sadun via swift-evolution 
>>>> <[email protected] <mailto:[email protected]>> wrote:
>>>> 
>>>> 
>>>>> On Jun 14, 2017, at 11:46 PM, Dave Abrahams via swift-evolution 
>>>>> <[email protected] <mailto:[email protected]>> wrote:
>>>>> 
>>>>> 
>>>>> on Wed Jun 14 2017, Chris Lattner <[email protected] 
>>>>> <mailto:[email protected]>> wrote:
>>>>> 
>>>>>>> On Jun 14, 2017, at 10:11 AM, Erica Sadun via swift-evolution
>>>>>>> <[email protected] <mailto:[email protected]>> wrote:
>>>>>>> 
>>>>>>> Some pals and I have been kicking an idea around about introducing
>>>>>>> better ways to support the compiler in protocol extensions. We want
>>>>>> 
>>>>>>> to eliminate some hard-to-detect bugs. We've been brainstorming on
>>>>>>> how to do this without affecting backward compatibility and
>>>>>>> introducing a minimal impact on keywords.
>>>>>>> 
>>>>>>> We'd love to know what you think of our idea, which is to introduce
>>>>>>> "role" keywords. Roles allow the compiler to automatically check the
>>>>>>> intended use of a extension member definition against its protocol
>>>>>>> declarations, and emit errors, warnings, and fixits as needed.  We
>>>>>>> think it's a pretty straightforward approach that, if adopted,
>>>>>>> eliminates an entire category of bugs.
>>>>>>> 
>>>>>>> The draft proposal is here:
>>>>>>> https://gist.github.com/erica/14283fe18254489c1498a7069b7760c4 
>>>>>>> <https://gist.github.com/erica/14283fe18254489c1498a7069b7760c4>
>>>>>>> <https://gist.github.com/erica/14283fe18254489c1498a7069b7760c4 
>>>>>>> <https://gist.github.com/erica/14283fe18254489c1498a7069b7760c4>>
>>>>>>> 
>>>>>>> Thanks in advance for your thoughtful feedback,
>>>>>> 
>>>>>> +1 on the idea of this.  
>>>>> 
>>>>> ditto.  IMO it also makes the protocol extension much more expressive
>>>>> and easy to read.
>>>>> 
>>>>> -- 
>>>>> -Dave
>>>> 
>>>> 
>>>> Pull request: https://github.com/apple/swift-evolution/pull/724 
>>>> <https://github.com/apple/swift-evolution/pull/724>
>>>> 
>>>> -- E
>>>> 
>>>> _______________________________________________
>>>> swift-evolution mailing list
>>>> [email protected] <mailto:[email protected]>
>>>> https://lists.swift.org/mailman/listinfo/swift-evolution 
>>>> <https://lists.swift.org/mailman/listinfo/swift-evolution>
>>> 
>> 
> 

_______________________________________________
swift-evolution mailing list
[email protected]
https://lists.swift.org/mailman/listinfo/swift-evolution

Reply via email to