Many thanks to the review team for their interest in the proposal!

Gwendal Roué

> Le 12 mai 2016 à 00:44, Chris Lattner via swift-evolution 
> <[email protected]> a écrit :
> 
> Proposal link: 
> https://github.com/apple/swift-evolution/blob/master/proposals/0073-noescape-once.md
> 
> Hello Swift Community,
> 
> The review of SE-0073: "Marking closures as executing exactly once" ran from 
> May 3…9, 2016. The proposal is *rejected* for Swift 3.  
> 
> The feedback on the proposal was generally positive both from the community 
> and core team.  That said, it is being rejected for Swift 3 two reasons:
> 
> 1) The surface level syntax of @noescape needs to be reconsidered.  At the 
> minimum, we need to rename @noescape to @nonescaping for consistency with our 
> previously agreed attribute naming scheme.  However, it is also work 
> discussing whether @nonescaping should be the default: if so, the attribute 
> should actually become @escaping, and the functionality proposed in SE-0073 
> would be named @once.
> 
> 2) Separate from the surface level issues, the implementation underlying this 
> work has some significant challenges that are doable but would require major 
> engineering work.  Specifically, the definite initialization pass needs to 
> “codegen” booleans in some cases for conditional initialization/overwrite 
> cases, and these state values would have to be added to closure capture 
> lists.  This would require enough engineering work that it seems unlikely 
> that it would happen in the Swift 3 timeframe, and beyond that this could 
> theoretically be subsumed into a more general system that allowed 
> control-flow-like functions to have closures that break/continue/throw/return 
> out of their enclosing function, or a general macro system.
> 
> Overall, everyone desires the ability to produce more control-flow like 
> functions, but Swift 3 isn’t in a place where it can make sense to tackle 
> this work.
> 
> Many thanks to Félix Cloutier and Gwendal Roué for driving this discussion 
> and writing a great proposal.  I hope that this topic comes back up for 
> discussion in a future release.
> 
> -Chris Lattner
> Review Manager
> 
> 
> _______________________________________________
> swift-evolution mailing list
> [email protected]
> 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