Tree::Simple::Visitor::PostOrderTraversal - A Visitor for post-order traversal a Tree::Simple hierarchy


  use Tree::Simple::Visitor::PostOrderTraversal;

  # create an visitor
  my $visitor = Tree::Simple::Visitor::PostOrderTraversal->new();

  # pass our visitor to the tree

  # print our results
  print join ", " => $visitor->getResults();

  # this will print this:
  #   1.1.1 1.1 1.2 1 2.1 2 3.1 3
  # assuming your tree is like this:
  #   1
  #     1.1
  #       1.1.1
  #     1.2
  #   2
  #     2.1
  #   3
  #     3.1


Post-order traversal is a variation of the depth-first traversal in which the sub-tree's are processed before the parent. It is another alternative to Tree::Simple's traverse method which implements a depth-first, pre-order traversal.



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

includeTrunk ($boolean)

Based upon the value of $boolean, this will tell the visitor to include the trunk of the tree in the traversal 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 method returns the accumulated results of the application of the node filter to the tree.


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 information.


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, 2005 by Infinity Interactive, Inc.

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