[swift-evolution] Warning on the '(T...) -> U' to '(T...) -> ()' conversion

[Erica Sadun]

I sincerely apologize for the lack of professionalism in my response. I will try to maintain higher standards in future communication.

Best regards. -- E

> On Feb 8, 2016, at 9:41 PM, Vanderlei Martinelli <vmartinelli at alecrim.com> wrote:
> 
> @EricaSadun I’d like to say that many of us are not native English speakers. I had to find what is the meaning of “gimme” and “dunno”. And it is a good thing, so I can learn more English words and slangs. But at the same time sometimes I read these messages in a place where it is not possible to consult dictionaries or when I just do not have time to do this.
> 
> OK... Let’s explain the words:
> 
> gimme. noun. a thing that is very easy to perform or obtain, especially in a game or sport: the kick would hardly be a gimme in that wind
> 
> dunno. contraction. (I) do not know. origin mid 19th cent.: representing an informal pronunciation.
> 
> ;-)
> 
> Dunno, but the more we use internationally known words may be a gimme to track the subject that is Swift evolution.
> 
> 
> On Tue, Feb 9, 2016 at 1:47 AM, Erica Sadun via swift-evolution <swift-evolution at swift.org <mailto:swift-evolution at swift.org>> wrote:
> 
> > On Feb 8, 2016, at 8:32 PM, Joe Groff via swift-evolution <swift-evolution at swift.org <mailto:swift-evolution at swift.org>> wrote:
> >
> >
> >> On Feb 8, 2016, at 7:25 PM, Joe Groff via swift-evolution <swift-evolution at swift.org <mailto:swift-evolution at swift.org>> wrote:
> >>
> >> Javier Soto brought up a case where his ReactiveCocoa code silently did the wrong thing by implicitly discarding the result of a closure:
> >>
> >> https://twitter.com/Javi/status/695680700033306624 <https://twitter.com/Javi/status/695680700033306624>
> >>
> >> Since it sounds like we plan on making `@warn_unused_result` the default, it seems natural to also warn when a closure has its result type converted away to Void. If there's one 'return' statement, we could dive into the return expression to decide whether to warn based on the function whose result is getting ignored.
> >
> > There's another axis of intent in whether the closure was written with an explicit return or not. `{ foo($0) }` is ambivalent to whether it intends to propagate the value returned by `foo` or not, whereas `{ return foo($0) }` is explicitly trying to do so. IMO we have a stronger case to warn if the `return` is explicit in the closure body.
> 
> 
> if foo  is -> Void, it's a gimme.
> if foo is -> T with @warn_unused_result, it's a gimme
> if foo is -> T without @warn_unused_result, dunno
> 
> -- E
> 
> _______________________________________________
> swift-evolution mailing list
> swift-evolution at swift.org <mailto:swift-evolution at swift.org>
> https://lists.swift.org/mailman/listinfo/swift-evolution <https://lists.swift.org/mailman/listinfo/swift-evolution>
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-evolution/attachments/20160208/5083f0a4/attachment.html>