Re: [swift-users] Compact iteration of optional collection?

On 28 Jul 2016, at 22:55, Rick Mann via swift-users wrote: > I often call methods that return an optional collection. Why do these methods return an optional collection rather an empty collection? Back in the day Cocoa code used to work that way because constructing

Re: [swift-users] Compact iteration of optional collection?

Like Rick, I had also wondered about a simple way to do this. Perhaps this is a question for swift-evolution, but wouldn’t it be desirable if Swift supported: for item in someOptionalContainer? { } which seems more natural and intuitive that the alternatives that have been suggested. Kerry

Re: [swift-users] Compact iteration of optional collection?

You can try container?.forEach(), like let bb:[String:Int]? = ["aa":1, "bb":2, "cc":3] bb?.forEach { print($0) } /* ("aa", 1) ("bb", 2) ("cc", 3) */ Zhaoxin On Fri, Jul 29, 2016 at 6:14 AM, Saagar Jha via swift-users < swift-users@swift.org> wrote: > The nil check and creating an empty

Re: [swift-users] Compact iteration of optional collection?

The nil check and creating an empty array have very similar performance, in my naïve testing. Saagar Jha > On Jul 28, 2016, at 14:59, Jacob Bandes-Storch via swift-users > wrote: > > You should test it out — I'd guess there's a good chance it gets optimized > out.

Re: [swift-users] Compact iteration of optional collection?

You should test it out — I'd guess there's a good chance it gets optimized out. On Thu, Jul 28, 2016 at 2:58 PM Rick Mann wrote: > Yeah, I suppose that works. Feels a bit clunky, like the language lacks > specific support for this (in that it provides specific support for

Re: [swift-users] Compact iteration of optional collection?

Yeah, I suppose that works. Feels a bit clunky, like the language lacks specific support for this (in that it provides specific support for so many other common constructs). But I guess I can make do with that. I suppose there's a bit of a performance hit, in that constructing an empty array

Re: [swift-users] Compact iteration of optional collection?

How about "for item in someOptionalContainer ?? []" ? On Thu, Jul 28, 2016 at 2:55 PM, Rick Mann via swift-users < swift-users@swift.org> wrote: > I often call methods that return an optional collection. I then iterate > over it. The problem is, it's a bit cumbersome to write: > > if let