title: NSCalendarUnit: is NSCalendarUnitNanosecond a valid enum value for NSCalendarUnit or not?
body: <p>I have a switch/case section of code in an iOS project that checks a variable of type NSCalendarUnit. At first, Xcode 5.0.2 gives a warning about not including some of the enum values in switch statements. So I added the rest of them, except NSCalendarUnitNanosecond, which Xcode indicates is not available in for iOS, and even puts a red strikethrough line through it when showing the auto-completion selections. Yet, Xcode 5.0.2 is still giving me the warning</p>
  
  <blockquote>
    <p>Enumeration value 'NSCalendarUnitNanosecond' not handled in switch</p>
  </blockquote>
  
  <p>So is it valid for iOS or not?</p>
  
  <p>(it's part of Mac OS X, e.g., <a href="https://developer.apple.com/library/mac/releasenotes/General/APIDiffsMacOSX10_9/Foundation.htm" rel="nofollow">https://developer.apple.com/library/mac/releasenotes/General/APIDiffsMacOSX10_9/Foundation.htm</a></p>
  
  <p>As a side note, it's interesting that the Apple docs at <a href="https://developer.apple.com/library/mac/documentation/cocoa/reference/foundation/classes/NSCalendar_Class/History/History.html#//apple_ref/doc/uid/TP40003626-RH1-SW1" rel="nofollow">https://developer.apple.com/library/mac/documentation/cocoa/reference/foundation/classes/NSCalendar_Class/History/History.html#//apple_ref/doc/uid/TP40003626-RH1-SW1</a> are out of date, being last updated in 2011.</p>