 For this example, we'll
    use <code>NSBackingStoreBuffered</code>:</p>

    <pre>
(ns:with-ns-rect (r 100 100 400 300)
  (#/initWithContentRect:styleMask:backing:defer: 
   my-window 
   r 
   (logior  #$NSTitledWindowMask 
            #$NSClosableWindowMask  
            #$NSMiniaturizableWindowMask 
            #$NSResizableWindowMask)
   #$NSBackingStoreBuffered
   ...))
    </pre>

    <p>Finally, the <code>defer</code> argument is just a Boolean. If
    we pass a true value, Cocoa will defer display