> On Oct 25, 2017, at 12:01, David Sweeris <daveswee...@mac.com> wrote:
>
>
>> On Oct 25, 2017, at 5:29 AM, David Zarzycki via swift-dev
>> <swift-dev@swift.org <mailto:swift-dev@swift.org>> wrote:
>>
>>
>>
>>> On Oct 25, 2017, at 02:34, Xiaodi Wu via swift-dev <swift-dev@swift.org
>>> <mailto:swift-dev@swift.org>> wrote:
>>>
>>> Please see earlier replies summarizing core team members' persuasive
>>> arguments as to why not multiple protocol hierarchies like this.
>>
>> Hi Xiaodi,
>>
>> The above line is does it help your argument. Even if a person was motivated
>> to search through the entire mailing list archives looking for said
>> arguments, they won’t be able to guess which arguments you found to be
>> persuasive (and who was sufficiently “core” at the time, no less). Can you
>> please provide URLs into the archives? Is that a big ask?
>
> If I'm (now) reading this correctly, he put the argument itself at the end of
> his earlier reply to you:
Right, to which I replied that I wasn’t proposing the Rust model or your
similar “MaybeEquatable” model. I was proposing something different where Float
and Int are both Equatable and Substitutable, but neither Equatable nor
Substitutable inherit from the other. The former is mathematical and the latter
is not (which allows it to deal with NaN payloads, ±0, etc). Generic algorithms
care mostly if not completely about mathematics, while generic containers care
mostly if not completely about substitutability. They can live alongside each
other and get along peacefully/sanely. And if people need to care about both,
then at least they have an out.
Dave
_______________________________________________
swift-dev mailing list
swift-dev@swift.org
https://lists.swift.org/mailman/listinfo/swift-dev
