I always yield to proof ;-) hope someone more knowledgable chips in...
Regards, Rien Site: http://balancingrock.nl Blog: http://swiftrien.blogspot.com Github: http://github.com/Balancingrock Project: http://swiftfire.nl > On 24 Mar 2017, at 11:53, Toni Suter <tonisu...@me.com> wrote: > > Hmm, I don't know. It also works with other nominal types. For example: > > struct S { > var x: Int > var y: Int > } > let s1 = S(x: 0, y: 1) > let s2 = S(x: 2, y: 3) > let arr = [s1, nil, s2] > print(type(of: arr)) // Array<Optional<S>> > >> Am 24.03.2017 um 11:30 schrieb Rien <r...@balancingrock.nl>: >> >> Btw, I just looked it up and it seems to me that inference only works for >> literals. Which probably means that tuples are out. >> >> Regards, >> Rien >> >> Site: http://balancingrock.nl >> Blog: http://swiftrien.blogspot.com >> Github: http://github.com/Balancingrock >> Project: http://swiftfire.nl >> >> >> >> >> >>> On 24 Mar 2017, at 11:22, Rien via swift-users <swift-users@swift.org> >>> wrote: >>> >>> IMO this is a boundary problem. >>> How far do you want to go in letting the compiler deduce the actual type? >>> It is possible to make very elaborate constructs that would basically >>> default to a complex tuple/array/dictionary construct with only Any?’s in >>> them. (well, the dict would require a Hashable too) >>> >>> Besides, the recent discussion on compile times illustrates another angle >>> to this problem: if type inference is used extensively, compile times go to >>> infinite… >>> >>> So while I do not know if this is a bug or not, I would recommend not to >>> use it anyhow. >>> >>> Regards, >>> Rien >>> >>> Site: http://balancingrock.nl >>> Blog: http://swiftrien.blogspot.com >>> Github: http://github.com/Balancingrock >>> Project: http://swiftfire.nl >>> >>> >>> >>> >>> >>>> On 24 Mar 2017, at 11:08, Toni Suter via swift-users >>>> <swift-users@swift.org> wrote: >>>> >>>> Hi, >>>> >>>> If I declare a variable and initialize it with an array literal whose >>>> elements are integer literals and nil literals, >>>> the compiler will infer the type Array<Optional<Int>> for that variable: >>>> >>>> let arr = [1, nil, 3] >>>> print(type(of: arr)) // Array<Optional<Int>> >>>> >>>> However, that only works with nominal types such as Int and String. If I >>>> do the same thing with an array of tuples, >>>> I get a compile error: >>>> >>>> let arr = [(1, false), nil, (3, true)] // error: type of >>>> expression is ambiguous without more context >>>> print(type(of: arr)) >>>> >>>> Why can't the compiler infer the type Array<Optional<(Int, Bool)>> in this >>>> example? Is there a reason for this or is it a bug? >>>> >>>> Thanks and best regards, >>>> Toni >>>> >>>> _______________________________________________ >>>> swift-users mailing list >>>> swift-users@swift.org >>>> https://lists.swift.org/mailman/listinfo/swift-users >>> >>> _______________________________________________ >>> swift-users mailing list >>> swift-users@swift.org >>> https://lists.swift.org/mailman/listinfo/swift-users >> > _______________________________________________ swift-users mailing list swift-users@swift.org https://lists.swift.org/mailman/listinfo/swift-users
