Commit | Line | Data |
3fea05b9 |
1 | |
2 | package Tree::Simple::Visitor::ToNestedArray; |
3 | |
4 | use strict; |
5 | use warnings; |
6 | |
7 | our $VERSION = '0.02'; |
8 | |
9 | use Scalar::Util qw(blessed); |
10 | |
11 | use base qw(Tree::Simple::Visitor); |
12 | |
13 | sub new { |
14 | my ($_class) = @_; |
15 | my $class = ref($_class) || $_class; |
16 | my $visitor = {}; |
17 | bless($visitor, $class); |
18 | $visitor->_init(); |
19 | return $visitor; |
20 | } |
21 | |
22 | sub visit { |
23 | my ($self, $tree) = @_; |
24 | (blessed($tree) && $tree->isa("Tree::Simple")) |
25 | || die "Insufficient Arguments : You must supply a valid Tree::Simple object"; |
26 | # grab our filter (if we have one) |
27 | my $filter = $self->getNodeFilter(); |
28 | my @results; |
29 | # get the array |
30 | $self->_buildArray($tree, \@results, $filter); |
31 | # add the trunk if we need to |
32 | @results = ( |
33 | ((defined($filter)) ? |
34 | $filter->($tree) |
35 | : |
36 | $tree->getNodeValue()), |
37 | [ @results ] |
38 | ) if $self->includeTrunk(); |
39 | # set results |
40 | $self->setResults(\@results); |
41 | } |
42 | |
43 | sub _buildArray { |
44 | my ($self, $tree, $accumulator, $filter) = @_; |
45 | foreach my $child ($tree->getAllChildren()) { |
46 | push @{$accumulator} => (defined($filter) ? $filter->($child) : $child->getNodeValue()); |
47 | push @{$accumulator} => $self->_buildArray($child, [], $filter) unless $child->isLeaf(); |
48 | } |
49 | return $accumulator; |
50 | } |
51 | |
52 | 1; |
53 | |
54 | __END__ |
55 | |
56 | =head1 NAME |
57 | |
58 | Tree::Simple::Visitor::ToNestedArray - A Visitor for creating nested array trees from Tree::Simple objects. |
59 | |
60 | =head1 SYNOPSIS |
61 | |
62 | use Tree::Simple::Visitor::ToNestedArray; |
63 | |
64 | my $visitor = Tree::Simple::Visitor::ToNestedArray->new(); |
65 | |
66 | # given this Tree::Simple tree |
67 | my $tree = Tree::Simple->new("Root") |
68 | ->addChildren( |
69 | Tree::Simple->new("Child1") |
70 | ->addChildren( |
71 | Tree::Simple->new("GrandChild1"), |
72 | Tree::Simple->new("GrandChild2") |
73 | ), |
74 | Tree::Simple->new("Child2"), |
75 | ); |
76 | |
77 | # include the trunk (Root) |
78 | $visitor->includeTrunk(1); |
79 | |
80 | # visit the tree |
81 | $tree->accept($visitor); |
82 | |
83 | my $array_tree = $visitor->getResults(); |
84 | # this then creates the equivalent nested array tree: |
85 | # [ |
86 | # 'Root', [ |
87 | # 'Child1', [ |
88 | # 'GrandChild1', |
89 | # 'GrandChild2' |
90 | # ], |
91 | # 'Child2' |
92 | # ] |
93 | # ] |
94 | |
95 | # if you don't include the trunk (Root) then ... |
96 | $tree->accept($visitor); |
97 | |
98 | my $array_tree = $visitor->getResults(); |
99 | # this then creates the following nested array tree: |
100 | # [ |
101 | # 'Child1', [ |
102 | # 'GrandChild1', |
103 | # 'GrandChild2' |
104 | # ], |
105 | # 'Child2' |
106 | # ] |
107 | |
108 | =head1 DESCRIPTION |
109 | |
110 | Given a tree constructed from a Tree::Simple heirarchy, this Visitor will create the equivalent tree of nested arrays. |
111 | |
112 | =head1 METHODS |
113 | |
114 | =over 4 |
115 | |
116 | =item B<new> |
117 | |
118 | There are no arguments to the constructor the object will be in its default state. You can use the C<setNodeFilter> and C<includTrunk> methods to customize its behavior. |
119 | |
120 | =item B<includTrunk ($boolean)> |
121 | |
122 | Setting the C<$boolean> value to true (C<1>) will cause the node value of the tree's root to be included in the nested array output, setting it to false will do the opposite. |
123 | |
124 | =item B<setNodeFilter ($filter_function)> |
125 | |
126 | This method accepts a CODE reference as its C<$filter_function> argument and throws an exception if it is not a code reference. This code reference is used to filter the tree nodes as they are placed into the array tree. The C<$filter_function> is passed a Tree::Simple object, and is expected to return the value desired for inclusion into the array tree. |
127 | |
128 | =item B<visit ($tree)> |
129 | |
130 | This is the method that is used by Tree::Simple's C<accept> method. It can also be used on its own, it requires the C<$tree> argument to be a Tree::Simple object (or derived from a Tree::Simple object), and will throw and exception otherwise. |
131 | |
132 | =item B<getResults> |
133 | |
134 | This method will return the array tree constructed. |
135 | |
136 | =back |
137 | |
138 | =head1 BUGS |
139 | |
140 | None that I am aware of. Of course, if you find a bug, let me know, and I will be sure to fix it. |
141 | |
142 | =head1 CODE COVERAGE |
143 | |
144 | See the B<CODE COVERAGE> section in L<Tree::Simple::VisitorFactory> for more inforamtion. |
145 | |
146 | =head1 SEE ALSO |
147 | |
148 | 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. |
149 | |
150 | =head1 AUTHOR |
151 | |
152 | stevan little, E<lt>stevan@iinteractive.comE<gt> |
153 | |
154 | =head1 COPYRIGHT AND LICENSE |
155 | |
156 | Copyright 2004, 2005 by Infinity Interactive, Inc. |
157 | |
158 | L<http://www.iinteractive.com> |
159 | |
160 | This library is free software; you can redistribute it and/or modify |
161 | it under the same terms as Perl itself. |
162 | |
163 | =cut |