/usr/share/perl5/Tree/Simple/Visitor/GetAllDescendents.pm is in libtree-simple-visitorfactory-perl 0.15-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 | package Tree::Simple::Visitor::GetAllDescendents;
use strict;
use warnings;
our $VERSION = '0.15';
use Scalar::Util qw(blessed);
use base qw(Tree::Simple::Visitor);
sub new {
my ($_class) = @_;
my $class = ref($_class) || $_class;
my $visitor = {};
bless($visitor, $class);
$visitor->_init();
return $visitor;
}
sub _init {
my ($self) = @_;
$self->{traversal_method} = undef;
$self->SUPER::_init();
}
sub setTraversalMethod {
my ($self, $visitor) = @_;
(blessed($visitor) && $visitor->isa("Tree::Simple::Visitor"))
|| die "Insufficient Arguments : You must supply a valid Tree::Simple::Visitor object";
$self->{traversal_method} = $visitor;
}
sub visit {
my ($self, $tree) = @_;
(blessed($tree) && $tree->isa("Tree::Simple"))
|| die "Insufficient Arguments : You must supply a valid Tree::Simple object";
# create an closure for the
# collection function
my @descendents;
my $filter_function = $self->getNodeFilter();
# build a collection function
my $collection_function = sub {
my ($t) = @_;
push @descendents => ($filter_function ?
$filter_function->($t)
:
$t->getNodeValue());
};
# and collect our descendents with the
# traversal method specified
unless (defined($self->{traversal_method})) {
$tree->traverse($collection_function);
}
else {
$self->{traversal_method}->setNodeFilter($collection_function);
$self->{traversal_method}->visit($tree);
}
# now store our collected descendents
$self->setResults(@descendents);
}
sub getAllDescendents {
my ($self) = @_;
return $self->getResults();
}
1;
__END__
=head1 NAME
Tree::Simple::Visitor::GetAllDescendents - A Visitor for fetching all the descendents of a Tree::Simple object
=head1 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 $t->getNodeValue()->description();
});
=head1 DESCRIPTION
Given a Tree::Simple instance this Visitor will return all the descendents recursively on down the hierarchy.
=head1 METHODS
=over 4
=item B<new>
There are no arguments to the constructor the object will be in its default state. You can use the C<setNodeFilter> method to customize its behavior.
=item B<setTraversalMethod ($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 C<$visitor> object implementing that traversal type to this method (See B<Tree::Simple::Visitor::BreadthFirstTraversal>, B<Tree::Simple::Visitor::PreOrderTraversal> and B<Tree::Simple::Visitor::PostOrderTraversal>).
=item B<setNodeFilter ($filter_function)>
This method accepts a CODE reference as its C<$filter_function> argument and throws an exception if it is not a code reference. This code reference is used to filter the tree nodes as they are collected. This can be used to customize output, or to gather specific information from a more complex tree node. The filter function should accept a single argument, which is the current Tree::Simple object.
=item B<visit ($tree)>
This is the method that is used by Tree::Simple's C<accept> method. It can also be used on its own, it requires the C<$tree> argument to be a Tree::Simple object (or derived from a Tree::Simple object), and will throw and exception otherwise.
=item B<getAllDescendents>
This method will give back and array of descendents in depth-first order (pre-order) or in the order specified by the C<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 C<getResults>.
=back
=head1 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.
=head1 CODE COVERAGE
See the B<CODE COVERAGE> section in L<Tree::Simple::VisitorFactory> for more information.
=head1 SEE ALSO
These Visitor classes are all subclasses of B<Tree::Simple::Visitor>, which can be found in the B<Tree::Simple> module, you should refer to that module for more information.
=head1 AUTHOR
stevan little, E<lt>stevan@iinteractive.comE<gt>
=head1 COPYRIGHT AND LICENSE
Copyright 2004, 2005 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
=cut
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