Stevan Little


Tree::Simple::Visitor::PathToRoot - A Visitor for finding the path back a Tree::Simple object's root


  use Tree::Simple::Visitor::PathToRoot;
  # create an instance of our visitor
  my $visitor = Tree::Simple::Visitor::PathToRoot->new();
  # pass the visitor to a Tree::Simple object
  # now get the accumulated path as a string 
  # with the '/' character as the delimiter
  print $visitor->getPathAsString("/");
  # include the tree's trunk in your
  # output as well 
  # for more complex node objects, you can specify 
  # a node filter which will be used to extract the
  # information desired from each node
  $visitor->setNodeFilter(sub { 
                my ($t) = @_;
                return $t->getNodeValue()->description();
  # you can also get the path back as an array
  my @path = $visitor->getPath();  


Given a Tree::Simple object, this Visitor will find the path back to the tree's root node.



There are no arguments to the constructor the object will be in its default state. You can use the includeTrunk and setNodeFilter methods to customize its behavior.

includeTrunk ($boolean)

Based upon the value of $boolean, this will tell the visitor to collect the trunk of the tree as well.

setNodeFilter ($filter_function)

This method accepts a CODE reference as its $filter_function argument and throws an exception if it is not a code reference. This code reference is used to filter the tree nodes as they are collected. This can be used to customize output, or to gather specific information from a more complex tree node. The filter function should accept a single argument, which is the current Tree::Simple object.

visit ($tree)

This is the method that is used by Tree::Simple's accept method. It can also be used on its own, it requires the $tree argument to be a Tree::Simple object (or derived from a Tree::Simple object), and will throw and exception otherwise.


This will return the collected path as an array, or in scalar context, as an array reference.

getPathAsString ($delimiter)

This will return the collected path as a string with the path elements joined by a $delimiter. If no $delimiter is specified, the default (', ') will be used.


None that I am aware of. Of course, if you find a bug, let me know, and I will be sure to fix it.


See the CODE COVERAGE section in Tree::Simple::VisitorFactory for more inforamtion.


These Visitor classes are all subclasses of Tree::Simple::Visitor, which can be found in the Tree::Simple module, you should refer to that module for more information.


stevan little, <>


Copyright 2004 by Infinity Interactive, Inc.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.