Prado\Xml\TXmlElementList::insertAt PHP Method

    public function insertAt($index, $item)
    {
        if ($item instanceof TXmlElement) {
            parent::insertAt($index, $item);
            if ($item->getParent() !== null) {
                $item->getParent()->getElements()->remove($item);
            }
            $item->setParent($this->_o);
        } else {
            throw new TInvalidDataTypeException('xmlelementlist_xmlelement_required');
        }
    }

 public function testRemoveAt()
 {
     $element = new TXmlElement('tag');
     $list = new TXmlElementList($element);
     $newElement = new TXmlElement('newTag');
     $list->insertAt(0, $newElement);
     self::assertEquals($newElement, $list->removeAt(0));
 }