angular $watch count

(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);
})();