/**
* Import a key-less imported value.
*
* @param $value
*
* @return array
* @throws \InvalidArgumentException
*/
protected function mergeValue($value)
{
if (Lib::is_assoc($value)) {
return $this->items = array_merge($this->items, $value);
} else {
throw new \InvalidArgumentException('Import failed due to malformed source or missing key.');
}
}
