PHP Pharborist Node::parents示例

 /**
  * Determines which currently-open file a node belongs to, if any. Nodes
  * which are not part of any open syntax tree will return NULL.
  *
  * @return string|NULL
  */
 public function getFileOf(Node $node)
 {
     if ($node instanceof RootNode) {
         $root = $node;
     } else {
         $parents = $node->parents();
         if ($parents->isEmpty()) {
             return NULL;
         }
         $root = $parents->get(0);
     }
     foreach ($this->documents as $file => $doc) {
         if ($root === $doc) {
             return $file;
         }
     }
 }