function get_my_bag_quantity(array_of_ids_to_update)
{
  if (!array_of_ids_to_update) {
    array_of_ids_to_update = new Array();
  }
  
  $.ajax({
    type: 'GET',
    url: '/cart/ajax_my_bag',
    data: {
      // nothing to send
    },
    dataType: 'json',
    timeout: 8000,
    success: function(json) {
      if (json.error) {
        alert(json.error);
      } else {
        
        // always update these
        $('#my_bag').html(json.html);
        $('#my_bag_footer').html(json.html);
        for (var i=0; i< array_of_ids_to_update.length; i++) {
          $('#' + array_of_ids_to_update[i]).html(json.html);
        }
      }
    }
  });
}

$(document).ready(function() { 
  get_my_bag_quantity();  
});