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Tree::Simple::Visitor:UsermContributedrPe::Simple::Visitor::FromNestedArray(3)

NAME
       Tree::Simple::Visitor::FromNestedArray -	A Visitor for creating
       Tree::Simple objects from nested	array trees.

SYNOPSIS
	 use Tree::Simple::Visitor::FromNestedArray;

	 my $visitor = Tree::Simple::Visitor::FromNestedArray->new();

	 # given this nested array tree
	 my $array_tree	= [
			   'Root', [
			       'Child1', [
				       'GrandChild1',
				       'GrandChild2'
				       ],
			       'Child2'
			       ]
			   ];
	 # set the array tree we
	 # are going to	convert
	 $visitor->setArrayTree($array_tree);

	 $tree->accept($visitor);

	 # this	then creates the equivalent Tree::Simple object:
	 # Tree::Simple->new("Root")
	 #     ->addChildren(
	 #	   Tree::Simple->new("Child1")
	 #	       ->addChildren(
	 #		   Tree::Simple->new("GrandChild1"),
	 #		   Tree::Simple->new("GrandChild2")
	 #	       ),
	 #	   Tree::Simple->new("Child2"),
	 #     );

DESCRIPTION
       Given a tree constructed	from nested arrays, this Visitor will create
       the equivalent Tree::Simple hierarchy.

METHODS
       new There are no	arguments to the constructor the object	will be	in its
	   default state. You can use the "setNodeFilter", "includTrunk" and
	   "setArrayTree" methods to customize its behavior.

       includTrunk ($boolean)
	   Setting the $boolean	value to true (1) will cause the node value of
	   the $tree object passed into	"visit"	to be set with the root	value
	   found in the	$array_tree. Setting it	to false (0), or not setting
	   it, will result in the first	value in the $array_tree creating a
	   new node level.

       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
	   created, the	$filter_function is passed the node value extracted
	   from	the array prior	to it being inserted into the tree being
	   built. The $filter_function is expected to return the value desired
	   for inclusion into the tree.

       setArrayTree ($array_tree)
	   This	method is used to set the $array_tree that our Tree::Simple
	   hierarchy will be constructed from. It must be in the following
	   form:

	     [
	       'Root', [
		   'Child1', [
			 'GrandChild1',
			 'GrandChild2'
			 ],
		   'Child2'
		 ]
	     ]

	   Basically each element in the array is considered a node, unless it
	   is an array reference, in which case	it is interpreted as
	   containing the children of the node created from the	previous
	   element in the array.

	   The tree is validated prior being accepted, if it fails validation
	   an exception	will be	thrown.	The rules are as follows;

	   The array tree must not be empty.
	       It makes	not sense to create a tree out of nothing, so it is
	       assumed that this is a sign of something	wrong.

	   All nodes of	the array tree must not	be array references.
	       The root	node is	validated against this in this function, but
	       all subsequent nodes are	checked	as the tree is built. Any
	       nodes found to be array references are rejected and an
	       exception is thrown. If you desire your node values to be array
	       references, you can use the node	filtering mechanism to achieve
	       this as the node	is filtered after it is	validated.

	   The array tree must be a single rooted tree.
	       If there	is a second element in the array tree, it is assumed
	       to be the children of the root, and therefore must be in	the
	       form of an array	reference.

       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.

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
       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.

perl v5.32.0			  201Tree::Simple::Visitor::FromNestedArray(3)

NAME | SYNOPSIS | DESCRIPTION | METHODS | BUGS | CODE COVERAGE | SEE ALSO | AUTHOR | COPYRIGHT AND LICENSE

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