Mixing Swift and Objective-C in a framework and private headers

Using Swift
7

We finally had success in Xcode 11 using:

  • add a custom MyFramework.modulemap 
framework module MyFramework {
	umbrella header "MyFramework.h"
	export *

	explicit module Private {
           header "MyPrivateHeader.h"
           header "MyPrivateOtherHeader.h"
        }
}
  • Mark all private headers as "Private", instead of "Project" inside your framework
  • In your swift file, you can now import MyFramework.Private
  • To stop users of the framework from importing private stuff, we added a linter rule that errors on import MyFramework.Private while not being inside the framework project
  • Be aware that for this approach to work, you must import headers using < > brackets instead of quotes inside the (Obj-)C files in your framework. So, #import <MyFramework/MyPublicHeader.h> and #import <MyFramework/MyPrivateHeader.h>

We also tried this with Xcode 10, but that would either crash the compiler or result in a barrage of errors

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