     import UIKit
 
     extension UIDevice {
+        /// The current version of the operating system.
         public var systemVersion: Version? {
             return Version(self.systemVersion())
         }

        }
    }
    
    public init!(_ value: String) {
        self = Version.parse(value)!
    }

// MARK: Foundation Extensions

extension NSBundle {
    /// The marketing version number of the bundle.
    public var version : Version? {
        return self.versionFromInfoDicitionary(forKey: String(kCFBundleVersionKey))
    }
    
    /// The short version number of the bundle.
    public var shortVersion : Version? {
        return self.versionFromInfoDicitionary(forKey: "CFBundleShortVersionString")
    }
