public function addPersonFunctionLink(ChildPersonFunctionLink $l)
    {
        if ($this->collPersonFunctionLinks === null) {
            $this->initPersonFunctionLinks();
            $this->collPersonFunctionLinksPartial = true;
        }

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

        return $this;
    }