Xcode 8 syntax highlighting doesn't work

Question

The code above has correct syntax highlighting in Xcode 7. It is mix of Obj-C + Swift:

I\'ve updated project to support

Answer 1

It happened also to me with Xcode 8 GM but also lots of time when I used Xcode 7: sometimes the auto-complete feature and the syntax highlighting die without notice.

The only solution that it works for me is restart Xcode but a few times I needed to complete reboot my Mac; I still don't know exactly what causes this annoying problem.