---
name: "Tree::Simple::Visitor::BreadthFirstTraversal"
section: "3pm"
platform: "linux"
package: "libtree-simple-visitorfactory-perl"
version: "0.16-3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Tree::Simple::Visitor::BreadthFirstTraversal"
---

# Tree::Simple::Visitor::BreadthFirstTraversal(3pm)

A Visitor for breadth-first traversal a Tree::Simple hierarchy

## NAME

Tree::Simple::Visitor::BreadthFirstTraversal - A Visitor for breadth-first traversal a Tree::Simple hierarchy

## SYNOPSIS

```
  use Tree::Simple::Visitor::BreadthFirstTraversal;
  # create an visitor
  my $visitor = Tree::Simple::Visitor::BreadthFirstTraversal->new();
  # pass our visitor to the tree
  $tree->accept($visitor);
  # print our results
  print join ", " => $visitor->getResults();
  # this will print this:
  #   1, 2, 3, 1.1, 1.2, 2.1, 3.1, 1.1.1
  # assuming your tree is like this:
  #   1
  #     1.1
  #       1.1.1
  #     1.2
  #   2
  #     2.1
  #   3
  #     3.1
```

## DESCRIPTION

This implements a breadth-first traversal of a Tree::Simple hierarchy. This can be an alternative to the built in depth-first traversal of the Tree::Simple `"traverse"` method.

## METHODS

- **new**

  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 the Tree::Simple `"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.

- **getResults**

  This method returns the accumulated results of the application of the node filter to the tree.

## Repository

\<https://github.com/ronsavage/Tree-Simple-VisitorFactory\>

## SUPPORT

Bugs should be reported via the CPAN bug tracker at

\<https://github.com/ronsavage/Tree-Simple-VisitorFactory/issues\>

## CODE COVERAGE

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

## SEE ALSO

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.

## AUTHOR

stevan little, \<stevan@iinteractive.com\>

## COPYRIGHT AND LICENSE

Copyright 2004, 2005 by Infinity Interactive, Inc.

\<http://www.iinteractive.com\>

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