[swift-evolution] Code blocks and trailing closures

[Rien]

> On 15 Mar 2017, at 13:33, Nick Keets <nick.keets at gmail.com> wrote:
> 
> I think the word you are looking for is “confusing”, not “ambiguous”. Nothing is ambiguous
> about the code you wrote, but you could make an argument that you find it confusing (since this is something subjective).
> 

Agreed.

Rien.

> On Wed, Mar 15, 2017 at 12:35 PM, Rien via swift-evolution <swift-evolution at swift.org> wrote:
> What does the following code fragment do?
> 
> serverCert.write(to: certificateUrl) { showErrorInKeyWindow(message); return }
> 
> The only possible answer is: I don’t know.
> 
> The problem is finding out what the “return” statement will do.
> 
> Without knowing if the {...} is a code block or a trailing closure it is impossible to know what the return statement will do. It will either end the closure or it will end the function that contains this code block.
> 
> This could be disambiguated by using the same syntax as for lazy variables:
> 
> serverCert.write(to: serverCertificateUrl) { showErrorInKeyWindow(message: message); return }()
> 
> Now it is clear that the return statement will only terminate the (trailing) closure.
> 
> A question to the educators on the list: Is this a real problem?
> 
> Personally, I dislike this situation, but I am also ambivalent towards the solution I just described.
> 
> Regards,
> Rien
> 
> Site: http://balancingrock.nl
> Blog: http://swiftrien.blogspot.com
> Github: http://github.com/Balancingrock
> Project: http://swiftfire.nl
> 
> 
> 
> 
> 
> _______________________________________________
> swift-evolution mailing list
> swift-evolution at swift.org
> https://lists.swift.org/mailman/listinfo/swift-evolution
>