So here's what I ended up doing:

I discovered you could pass a function to $scope.$watch. From there, it's pretty straightforward to return the value of the expression you want to watch for changes. It will work exactly like passing a key string for a property on the scope.

link: function ($scope, $el, $attrs) {
  $scope.$watch(
    function () { return $el[0].childNodes.length; },
    function (newValue, oldValue) {
      if (newValue !== oldValue) {
        // code goes here
      }
    }
  );
}

I am watching childNodes, not children, because the childNodes list holds elements as well as text nodes and comments. This is priceless because Angular uses comment placeholders for directives like ng-repeat, ng-if, ng-switch and ng-include which perform transclusion and alter the DOM, while children only holds elements.


If you need to watch for any changes deeper in the element's dom, MutationObserver is the way to go :

.directive('myDirective', function() {
    return {
        ...
        link: function(scope, element, attrs) {
            var observer = new MutationObserver(function(mutations) {
                // your code here ...
            });
            observer.observe(element[0], {
                childList: true,
                subtree: true
            });
        }
    };
});

I created a directive module for this angular-dom-events

In your case you could

    <ul class="unstyled" auto-carousel>
      <li class="slide" ng-if="name" dom-on-create="nameCreated()">{{name}}</li>
      <li class="slide" ng-if="email" dom-on-destroy="emailDestroyed()">{{email}}</li>
    </ul>

Currently only supports dom-on-create and dom-on-destroy, but has better performance then the accepted answer because it will only fire once for each dom event, rather than repeatedly check the $watch callback.