Actually a fair bit is in Sierra. Apple decided apparently not to invest resources in targeting 32-bit platform support, so they have had to hold off shipping software relying on it until the platforms drop 32-bit support. Sierra did that last year, and I'd put $5 on iOS 11 doing that as well.
Correct, I should have said "the platforms dropping 32-bit processor support".
The ability to run 32-bit applications means that preexisting libraries cannot incorporate Swift code yet.
The "application may slow down your phone" warnings that users are getting with 32-bit apps this year is a pretty strong indicator that Apple is going to remove support for running 32-bit apps completely for iOS 11 or 12. They previously had a deadline for apps to have 64-bit version submitted, but backed off the ultimatum for now.
> They previously had a deadline for apps to have 64-bit version submitted, but backed off the ultimatum for now.
Apps have had to support 64-bit since June 2015 (February 2015 for new apps), and Apple hasn't backed off that deadline. But there are still 32-bit apps on the store that haven't received an 64-bit update, and I don't think Apple has ever stated what it is going to do about them (other than showing the warning).
Apple can't write Swift libraries (at least not ones that are publicly exposed) until the ABI stabilizes, so that will not happen until at least Swift 4. Apple can write Swift apps as long as they don't need to support 32-bit Mac, which they haven't needed to do for years.
Sierra did not drop support for 32-bit applications. Pretty sure Microsoft Office just released a 64-bit version of their product a month or two ago. Good luck dropping 32-bit on the Mac and godspeed.
Well that doesn't bode well ;) Sierra's dock is sooo buggy. I have to restart my machine numerous times a day because the dock stops working, literally doesn't work lol. I'm sure theres a way to restart just the dock app, but eh i've been quite busy. Sierra has been one of the buggiest version of Mac I can remember using.
I would surprised if they actually did tho. I know someone did some static analysis of the apps for mac and iOS and found Swift was barely used at all.