 		
 		for i in 1...n {
 
-			// load an instance of our SampleView
-			v = UINib(nibName: "SampleView", bundle: nil).instantiateWithOwner(nil, options: nil)[0] as! UIView
+			// load an instance of our SampleView... would have proper error handling in real-world-usage
+			guard let v = UINib(nibName: "SampleView", bundle: nil).instantiateWithOwner(nil, options: nil)[0] as? UIView else { return }
+			
 			v.translatesAutoresizingMaskIntoConstraints = false
 			
-			// the UILabel in our SampleView was assigned a Tag of 99 in IB
-			lbl = v.viewWithTag(99) as! UILabel
+			// the UILabel in our SampleView was assigned a Tag of 99 in IB... would have proper error handling in real-world-usage
+			guard let lbl = v.viewWithTag(99) as? UILabel else { return }
 			lbl.text = "\(i)"
 			
 			// add this view to the ScrollView

		var currRef: String
		var vFmt: String
		var hFmt: String
		
		var v: UIView
		var lbl: UILabel

		var dViews = [String:AnyObject]()
		

				
				// Center vertically in scroll view
				
				// first, set the height constraint of our SampleView
				vFmt = "V:[\(currRef)(height)]";
				self.theScrollView.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat(vFmt, options: [], metrics: dMetrics, views: dViews))

