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Tree::Simple::Visitor:UserdContributedePerlple::Visitor::LoadDirectoryTree(3)

NAME
       Tree::Simple::Visitor::LoadDirectoryTree	- A Visitor for	loading	the
       contents	of a directory into a Tree::Simple object

SYNOPSIS
	 use Tree::Simple::Visitor::LoadDirectoryTree;

	 # create a Tree::Simple object	whose
	 # node	is path	to a directory
	 my $tree = Tree::Simple->new("./");

	 # create an instance of our visitor
	 my $visitor = Tree::Simple::Visitor::LoadDirectoryTree->new();

	 # set the directory sorting style
	 $visitor->setSortStyle($visitor->SORT_FILES_FIRST);

	 # create node filter to filter
	 # out certain files and directories
	 $visitor->setNodeFilter(sub {
	     my	($item)	= @_;
	     return 0 if $item =~ /CVS/;
	     return 1;
	 });

	 # pass	the visitor to a Tree::Simple object
	 $tree->accept($visitor);

	 # the tree now	mirrors	the structure of the directory

DESCRIPTION
       This visitor can	be used	to load	a directory tree into a	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" and "setSortStyle"
	   methods to customize	its behavior.

       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	function is given the current directory	or file	being
	   added to the	tree, and it is	expected to return either true (1) of
	   false (0) to	determine if that directory should be traversed	or
	   file	added to the tree.

       setSortStyle ($sort_function)
	   This	method accepts a CODE reference	as its $sort_function argument
	   and throws an exception if it is not	a code reference. This
	   function is used to sort the	individual levels of the directory
	   tree	right before it	is added to the	tree being built. The function
	   is passed the current path, followed	by the two items being sorted.
	   The reason for passing the path in is so that sorting operations
	   can be performed on the entire path if desired.

	   Two pre-built functions are supplied	and described below.

	   SORT_FILES_FIRST
	       This sorting function will sort files before directories, so
	       that files are sorted alphabetically first in the list followed
	       by directories sorted alphabetically. Here is example of	how
	       that would look:

		   Tree/
		       Simple.pm
		       Simple/
			   Visitor.pm
			   VisitorFactory.pm
			   Visitor/
			       PathToRoot.pm

	   SORT_DIRS_FIRST
	       This sorting function will sort directories before files, so
	       that directories	are sorted alphabetically first	in the list
	       followed	by files sorted	alphabetically.	Here is	example	of how
	       that would look:

		   Tree/
		       Simple/
			   Visitor/
			       PathToRoot.pm
			   Visitor.pm
			   VisitorFactory.pm
		       Simple.pm

       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.

	   The node value of the $tree argument	(gotten	by calling
	   "getNodeValue") is considered the root directory from which we
	   begin our traversal.	We use File::Spec to keep our paths cross-
	   platform, but it is expected	that you will feed in a	valid path for
	   your	OS. If the path	either does not	exist, or is not a directory,
	   then	an exception is	thrown.

	   The $tree argument which is passed to "visit" must be a leaf	node.
	   This	is because this	Visitor	will create all	the sub-nodes for this
	   tree. If the	tree is	not a leaf, an exception is thrown. We do not
	   require the tree to be a root though, and this Visitor will not
	   affect any nodes above the $tree argument.

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			  2Tree::Simple::Visitor::LoadDirectoryTree(3)

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

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