Tree::Simple::Visitor::LoadDirectoryTree - A Visitor for loading the contents of a directory into a Tree::Simple object
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
This visitor can be used to load a directory tree into a Tree::Simple hierarchy.
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
setSortStyle
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.
$filter_function
1
0
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 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.
$sort_function
Two pre-built functions are supplied and described below.
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
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
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.
accept
$tree
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.
getNodeValue
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.
visit
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 inforamtion.
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, <stevan@iinteractive.com>
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.
To install Tree::Simple::VisitorFactory, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Tree::Simple::VisitorFactory
CPAN shell
perl -MCPAN -e shell install Tree::Simple::VisitorFactory
For more information on module installation, please visit the detailed CPAN module installation guide.