Tree::Simple::Visitor:UserAContribuTree::Simple::Visitor::GetAllDescendents(3)NAMETree::Simple::Visitor::GetAllDescendents - A Visitor for fetching all
the descendents of a Tree::Simple object
SYNOPSIS
use Tree::Simple::Visitor::GetAllDescendents;
# create an instance of our visitor
my $visitor = Tree::Simple::Visitor::GetAllDescendents->new();
# pass the visitor to a Tree::Simple object
$tree->accept($visitor);
# you can also get the descendents
# back as an array of node values
my @descendents = $visitor->getDescendents();
# 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 $t->getNodeValue()->description();
});
DESCRIPTION
Given a Tree::Simple instance this Visitor will return all the
descendents recursively on down the hierarchy.
METHODS
new There are no arguments to the constructor the object will be in its
default state. You can use the "setNodeFilter" method to customize
its behavior.
setTraversalMethod ($visitor)
By default we will use Tree::Simple's built in depth-first (pre-
order) traverse method. If however, you desire the descendents to
be returned in a different ordering, this can be accomplished using
a different traversal method, you can supply a $visitor object
implementing that traversal type to this method (See
Tree::Simple::Visitor::BreadthFirstTraversal,
Tree::Simple::Visitor::PreOrderTraversal and
Tree::Simple::Visitor::PostOrderTraversal).
setNodeFilter ($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.
getAllDescendents
This method will give back and array of descendents in depth-first
order (pre-order) or in the order specified by the
"setTraversalMethod". If called in scalar context it will give an
array reference, in list context it will return a regular array.
This method is the same as calling "getResults".
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::GetAllDescendents(3)
