> Am 29.06.2016 um 08:33 schrieb Jean-Daniel Dupas via swift-evolution > <swift-evolution@swift.org>: > > >> Le 29 juin 2016 à 01:01, Michael Peternell via swift-evolution >> <swift-evolution@swift.org> a écrit : >> >> >>> Am 29.06.2016 um 00:32 schrieb John McCall <rjmcc...@apple.com>: >>> >>> The decision to make class methods polymorphic by default was always >>> premised on being able to undo that in obvious cases where methods are >>> never overridden. Making a class public so that clients can use it >>> shouldn't cause significant performance degradations just because you >>> forgot to also write "final". >>> >>> John. >> >> I do care about performance. For this reason I don't want a fully dynamic >> language. I disagree about the "significant performance degradations just >> because you forgot to also write `final`". I mentioned "performance" in my >> original post only because it would be the only convincing argument - if >> there were indeed superior performance when using `final`. >> >> Of course, dynamic dispatch is much slower than static dispatch. But >> optimized code does not spend much time dispatching. If a method takes 3 >> seconds to complete, and from that 2 seconds are used for dynamically >> dispatching method calls, then I would say that it has not been optimized >> for performance yet. How would such a function look like? The function being >> dynamically dispatched should probably not be statically dispatched but >> inlined completely. And for the rare case that the dispatch type really >> makes all the difference, it's always possible to `final`ize (or >> `private`ize) some of the used methods. > > Swift dynamic dispatch is not Obj-C dynamic dispatch. Talking about the cost > of dynamic dispatch without real benchmark is premature optimization IMHO.
Whom are you telling this? And which do you think is faster? Objc dynamic dispatch or Swift dynamic dispatch? I think, in the long run, Swift dynamic dispatch will be faster because Swift is less dynamic on that level. -Michael _______________________________________________ swift-evolution mailing list swift-evolution@swift.org https://lists.swift.org/mailman/listinfo/swift-evolution
