Formal\Form\Morphology::remove PHP Method

    function remove($sPropName)
    {
        if (($sKey = $this->keyForPropName($sPropName)) === false) {
            throw new \Exception("\\Formal\\Form\\Morphology->element(): Element prop='" . $sPropName . "' not found");
        }
        $this->oElements->remove($sKey);
    }

 function morphologyHook(\Formal\Form $oForm, \Formal\Form\Morphology $oMorpho)
 {
     if ($oForm->submitted()) {
         $bMySQL = intval($oForm->postValue("PROJECT_DB_MYSQL")) === 1;
     } else {
         $bMySQL = PROJECT_DB_MYSQL;
     }
     if ($bMySQL === true) {
         $oMorpho->remove("PROJECT_SQLITE_FILE");
     } else {
         $oMorpho->remove("PROJECT_DB_MYSQL_HOST");
         $oMorpho->remove("PROJECT_DB_MYSQL_DBNAME");
         $oMorpho->remove("PROJECT_DB_MYSQL_USERNAME");
         $oMorpho->remove("PROJECT_DB_MYSQL_PASSWORD");
     }
 }