Tree::Simple::Visitor:UserdContribuTree::Simple::Visitor::LoadDirectoryTree(3)NAMETree::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 $sort_function argument
and throws an exception if it is not a code reference. This
function is used to sort the individual levels of the directory
tree right before it is added to the tree being built. The function
is passed the the current path, followed by the two items being
sorted. The reason for passing the path in is so that sorting
operations can be performed on the entire path if desired.
Two pre-built functions are supplied and described below.
SORT_FILES_FIRST
This sorting function will sort files before directories, so
that files are sorted alphabetically first in the list followed
by directories sorted alphabetically. Here is example of how
that would look:
Tree/
Simple.pm
Simple/
Visitor.pm
VisitorFactory.pm
Visitor/
PathToRoot.pm
SORT_DIRS_FIRST
This sorting function will sort directories before files, so
that directories are sorted alphabetically first in the list
followed by files sorted alphabetically. Here is example of how
that would look:
Tree/
Simple/
Visitor/
PathToRoot.pm
Visitor.pm
VisitorFactory.pm
Simple.pm
visit ($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
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 v5.14.12Tree::Simple::Visitor::LoadDirectoryTree(3)
