macOS Support

[brettrowberry]

I found that the tight coupling between SwiftUI and Apple's Translation API made making my app difficult. When I stumbled across this library, I was really excited. Would you be open to extending it to support macOS?

[brettrowberry]

I'm brand new to developing for Apple platforms, but when I tried to build against macOS with it, I think the only limitations were from UIKit test code.