Looping through subviews and downcasting in Swift

I've been playing around with Auto-Layout. This snippet was helpful to see what constraints were set on what views in my View Hierarchy.

Getting the downcast right on the subviews Array took a few tries:

```swift func showAL(view: UIView) { println("!") println(view) println(view.constraints()) }

for view in self.subviews as [UIView] {
    for subview in view.subviews as [UIView] {