In the ngDraggable project, I found this code in the directive ngDrag.
 attrs.$observe("ngDrag", onEnableChange);
 scope.$watch(attrs.ngDrag, onEnableChange);
 attrs.$observe('ngCenterAnchor', onCenterAnchor);
 scope.$watch(attrs.ngCenterAnchor, onCenterAnchor);
My question is:
Why would you need both the $observe and $watch properties on the same items?
I've tried commenting each group out and it seems to make no difference at all. What is going on here?
 
    