JavaScript all properties exist

propertiesExist = function(object, properties) {
  var allExist = true;
  properties = properties || {};

  Ext.each(properties, function(property) {
    var splits = property.split('.');
    var currentObj = object;
    Ext.each(splits, function(currentProperty, index, all) {
      if (!allExist) return false;

      currentObj = currentObj[currentProperty];
      if (!currentObj) allExist = false;
    });
  });
  
  return allExist;
}

//Usage
var myObj = {a: {b: {c: 'd'}}, '1': {'2': '3'}};
propertiesExist(myObj, 'a.b.c'); // => returns true
propertiesExist(myObj, 'a.b.c', '1.2'); //returns true
propertiesExist(myObj, 'd'); //returns false