public function addAttributeTypeAvMeta(ChildAttributeTypeAvMeta $l)
    {
        if ($this->collAttributeTypeAvMetas === null) {
            $this->initAttributeTypeAvMetas();
            $this->collAttributeTypeAvMetasPartial = true;
        }

        if (!in_array($l, $this->collAttributeTypeAvMetas->getArrayCopy(), true)) { // only add it if the **same** object is not already associated
            $this->doAddAttributeTypeAvMeta($l);
        }

        return $this;
    }