private function &recursiveBuildPreliminaryFormTree(FormInterface $form, array &$outputByHash)
{
$hash = spl_object_hash($form);
$output = &$outputByHash[$hash];
$output = isset($this->dataByForm[$hash])
? $this->dataByForm[$hash]
: array();
$output['children'] = array();
foreach ($form as $name => $child) {
$output['children'][$name] = &$this->recursiveBuildPreliminaryFormTree($child, $outputByHash);
}
return $output;
}