tree::redblack(3pm) [debian man page]

RedBlack(3pm)						User Contributed Perl Documentation					     RedBlack(3pm)

NAME

       Tree::RedBlack - Perl implementation of Red/Black tree, a type of balanced tree.

SYNOPSIS

	 use Tree::RedBlack;

	 my $t = new Tree::RedBlack;
	 $t->insert(3, 'cat');
	 $t->insert(4, 'dog');
	 my $v = $t->find(4);
	 my $min = $t->min;
	 my $max = $t->max;
	 $t->delete(3);
	 $t->print;

DESCRIPTION

       This is a perl implementation of the Red/Black tree algorithm found in the book "Algorithms", by Cormen, Leiserson & Rivest (more commonly
       known as "CLR" or "The White Book").  A Red/Black tree is a binary tree which remains "balanced"- that is, the longest length from root to
       a node is at most one more than the shortest such length.  It is fairly efficient; no operation takes more than O(lg(n)) time.

       A Tree::RedBlack object supports the following methods:

       new ()
	   Creates a new RedBlack tree object.

       root ()
	   Returns the root node of the tree.  Note that this will either be undef if no nodes have been added to the tree, or a
	   Tree::RedBlack::Node object.  See the Tree::RedBlack::Node manual page for details on the Node object.

       cmp (&)
	   Use this method to set a comparator subroutine.  The tree defaults to lexical comparisons.  This subroutine should be just like a
	   comparator subroutine to sort, except that it doesn't do the $a, $b trick; the two elements to compare will just be the first two items
	   on the stack.

       insert ($;$)
	   Adds a new node to the tree.  The first argument is the key of the node, the second is its value.  If a node with that key already
	   exists, its value is replaced with the given value and the old value is returned.  Otherwise, undef is returned.

       delete ($)
	   The argument should be either a node object to delete or the key of a node object to delete. WARNING!!! THIS STILL HAS BUGS!!!

       find ($)
	   Searches the tree to find the node with the given key.  Returns the value of that node, or undef if a node with that key isn't found.
	   Note, in particular, that you can't tell the difference between finding a node with value undef and not finding a node at all.  If you
	   want to determine if a node with a given key exists, use the node method, below.

       node ($)
	   Searches the tree to find the node with the given key.  Returns that node object if it is found, undef otherwise.  The node object is a
	   Tree::RedBlack::Node object.

       min ()
	   Returns the node with the minimal key.

       max ()
	   Returns the node with the maximal key.

AUTHOR

       Benjamin Holzman <bholzman@earthlink.net>

SEE ALSO

       Tree::RedBlack::Node

perl v5.10.0							    2008-07-31							     RedBlack(3pm)

Tree::Simple::Visitor::FindByPath(3pm)			User Contributed Perl Documentation		    Tree::Simple::Visitor::FindByPath(3pm)

NAME

       Tree::Simple::Visitor::FindByPath - A Visitor for finding an element in a Tree::Simple hierarchy with a path

SYNOPSIS

	 use Tree::Simple::Visitor::FindByPath;

	 # create a visitor object
	 my $visitor = Tree::Simple::Visitor::FindByPath->new();

	 # set the search path for our tree
	 $visitor->setSearchPath(qw(1 1.2 1.2.2));

	 # pass the visitor to a tree
	 $tree->accept($visitor);

	 # fetch the result, which will
	 # be the Tree::Simple object that
	 # we have found, or undefined
	 my $result = $visitor->getResult() || die "No Tree found";

	 # our result's node value should match
	 # the last element in our path
	 print $result->getNodeValue(); # this should print 1.2.2

DESCRIPTION

       Given a path and Tree::Simple hierarchy, this Visitor will attempt to find the node specified by the path.

METHODS

       new There are no arguments to the constructor the object will be in its default state. You can use the "setSearchPath" and "setNodeFilter"
	   methods 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 search as well.

       setSearchPath (@path)
	   This is the path we will attempt to follow down the tree. We will do a stringified comparison of each element of the path and the
	   current tree's node (or the value returned by the node filter if it is set).

       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.

       getResult
	   This method will return the tree found at the specified path (set by the "setSearchPath" method) or "undef" if no tree is found.

       getResults
	   This method will return the tree's that make up the path specified in "setSearchPath". In the case of a failed search, this can be used
	   to find the elements which did successfully match along the way.

BUGS

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

CODE COVERAGE

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

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.

perl v5.10.1							    2005-10-24				    Tree::Simple::Visitor::FindByPath(3pm)