Tree::Simple::Visitor::PathToRoot - A Visitor for finding the path back a
Tree::Simple object's root
use Tree::Simple::Visitor::PathToRoot;
# create an instance of our visitor
my $visitor = Tree::Simple::Visitor::PathToRoot->new();
# pass the visitor to a Tree::Simple object
$tree->accept($visitor);
# now get the accumulated path as a string
# with the '/' character as the delimiter
print $visitor->getPathAsString("/");
# include the tree's trunk in your
# output as well
$visitor->includeTrunk();
# for more complex node objects, you can specify
# a node filter which will be used to extract the
# information desired from each node
$visitor->setNodeFilter(sub {
my ($t) = @_;
return $t->getNodeValue()->description();
});
# you can also get the path back as an array
my @path = $visitor->getPath();
Given a Tree::Simple object, this Visitor will find the path back to the tree's
root node.
- new
- There are no arguments to the constructor the object will be in its
default state. You can use the
"includeTrunk" and
"setNodeFilter" methods to customize its
behavior.
- includeTrunk ($boolean)
- Based upon the value of $boolean, this will tell
the visitor to collect the trunk of the tree as well.
- setNodeFilter ($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 $tree argument to be a
Tree::Simple object (or derived from a Tree::Simple object), and will
throw and exception otherwise.
- getPath
- This will return the collected path as an array, or in scalar context, as
an array reference.
- getPathAsString ($delimiter)
- This will return the collected path as a string with the path elements
joined by a $delimiter. If no
$delimiter is specified, the default (', ') will
be used.
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
information.
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.