Ultimate Catalyst Guide

If you want to compile code that runs only on macOS, you can do that by using the following, new compile time attribute:

#if targetEnvironment(UIKitForMac)

   let toolbar = NSToolbar(identifier: \"MyToolbar\")

#endif

Obviously, to do it the other way around, you just inverse it:

#if !targetEnvironment(UIKitForMac)

   import ARKit

#endif