On Mon, 13 Nov 2017 22:30:25 +0100 David Hart <[email protected]> wrote:
> On 13 Nov 2017, at 05:52, Slava Pestov <[email protected]> wrote: > > > >> On Nov 12, 2017, at 8:11 PM, Brent Royal-Gordon via swift-evolution < > [email protected]> wrote: > >> > >> By analogy with the current closure syntax, the capture list ought to > go somewhere before the parameter list, in one of these slots: > >> > >> 1. func fn<T>[foo, bar](param: T) throws -> T where T: Equatable { … } > >> 2. func fn[foo, bar]<T>(param: T) throws -> T where T: Equatable { … } > >> 3. func [foo, bar] fn<T>(param: T) throws -> T where T: Equatable { … > } > >> 4. [foo, bar] func fn<T>(param: T) throws -> T where T: Equatable { … > } > >> > >> Of these options, I actually think #4 reads best; 1 and 2 are very > cluttered, and 3 just seems weird. But it seems like the one that would be > easiest to misparse. > > > > Another option that reads nicely IMHO is > > > > func fn<T>(param: T) throws -> T where T : Equatable [foo, bar] { … } > > > > I think #4 is ambiguous with array literals unfortunately. > adding to the list of options: 6. func fn<T>(param: T) throws -> T where T: Equatable [foo, bar] { … } otherwise +1 to #1 and to the one in proposal. also see about #4 below. plus, if 90%+ of use cases in practice would be [weak self] -- (the only examples shown in the proposals FTM) -- i would strongly consider this syntax sugar in addition to a generic notation: weak func fn<T>(param: T) throws -> T where T: Equatable { … } works with "unowned" as a bonus. if implement this sugar than some variation of #4 looks appealing to have these capture things close. Mike
_______________________________________________ swift-evolution mailing list [email protected] https://lists.swift.org/mailman/listinfo/swift-evolution
