Don't compile iOS in code for OSX on a cross-platform iOS/OSX module

Question

I'm building a module that will be used in a iOS/OSX app.

The client is insisting that the module work on both iOS and OSX.

I need to check the system version which I'm doing with UIDevice on iOS and on OSX I'm using FTWDevice.

The problem is that when I try to compile it on OSX it complains that OSX doesn't support UIDevice.

I'm wondering if there is a way I can tell the compiler to compile a line of code on iOS but not on OSX?

I know I can do this with this to compile something on production only:

#ifndef DEBUG
[Crashlytics startWithAPIKey:CRASHLYTICSKEY];
#endif

Is there a solution for this or should I tell the client they're gonna need 2 modules that are exactly the same except for one line?

Another acceptable solution would be a workaround for finding the system version on iOS that doesn't involve using UIDevice.

Answer 1

Look at TargetConditionals.h. Specifically:

#if TARGET_OS_MAC
 // Mac-only code here
#endif

#if TARGET_OS_IPHONE
 // iOS-only code here
#endif

Answer 2

Another acceptable solution would be a workaround for finding the system version on iOS that doesn't involve using UIDevice.

You can do as follow to obtain system version (OS X and iOS):

func majorVersion() -> Int    { return NSProcessInfo.processInfo().operatingSystemVersion.majorVersion }
func minorVersion() -> Int    { return NSProcessInfo.processInfo().operatingSystemVersion.minorVersion }
func patchVersion() -> Int    { return NSProcessInfo.processInfo().operatingSystemVersion.patchVersion }
func myOSVersion()  -> String { return NSProcessInfo.processInfo().operatingSystemVersionString }