Compiler will show mistakes when I do this:

#if os(iOS)
class AView: UIView {
#else
class AView: NSView {
#endif
    
}

Why can't I do this?

Does it have any methods to do this thing?

CodePudding user response：

Use conditional compiling with a typealias instead:

#if os(iOS)
typealias ParentView = UIView
#else
typealias ParentView = NSView
#endif

class AView: ParentView {}

Then you'll be able to extend that type alias.

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