AngularJS SafeApply. This fixes the annoying angular error: "Error: $digest already in progress"

safeapply.js

app.factory( 'SafeApply', function() {
  return function($scope, fn) {
    var phase = $scope.$root.$$phase;
    if(phase == '$apply' || phase == '$digest') {
      if(fn && (typeof(fn) === 'function')) {
        fn();
      }
    } else {
      $scope.$apply(fn);
    }
  }
});

Usage:

SafeApply( $scope, function(){
  $scope.cats = 'awesome';
});