Xcode code highlighting keeps crashing

Question

I'm building an iOS app using Swift. And recently, Xcode has been going crazy. My code highlighting keeps turning on and off (from colored variables to white on black ...) See print screens.

So in a couple of seconds, I go from

To this:

And then back to color. Sometime, the color doesn't come back for a couple of minutes. Any ideas how I can fix this?

Answer 1

Have this problem with Xcode 6.1 (release, not GM).

There a few "magic" solutions that works temporarily, but require a restart. There is quick fix that seems to hold (and does not require a complete restart).

Delete the content of: DerivedData/ModuleCache

(Full path: ~/Library/Developer/Xcode/DerivedData/ModuleCache)

Answer 2

In my opinion Xcode 6 is buggy with swift. It happen when there's some error in code or when Xcode hasn't already finished to indexing files. I didn't find solution to that, try to clean project and rebuild again, to avoid that i build my code after every new line of code -.- . The problem is resolved on Xcode 7 released yesterday (16-sep-2015).