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
