Determine number of angular watchers

gistfile1.js

(function() {
    var root = $(document.getElementsByTagName('body'));
    var watchers = [];
    var f = function(element) {
        if (element.data().hasOwnProperty('$scope')) {
            angular.forEach(element.data().$scope.$$watchers, function(watcher) {
                watchers.push(watcher);
            });
        }
        angular.forEach(element.children(), function(childElement) {
            f($(childElement));
        });
    };
    f(root);
    console.log(watchers.length);
})();