1Tree::Simple::Visitor::UFsreormNCeosntterdiAbrurtaeydT(r3Pe)eer:l:SDiomcpulmee:n:tVaitsiiotnor::FromNestedArray(3)
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NAME

6       Tree::Simple::Visitor::FromNestedArray - A Visitor for creating
7       Tree::Simple objects from nested array trees.
8

SYNOPSIS

10         use Tree::Simple::Visitor::FromNestedArray;
11
12         my $visitor = Tree::Simple::Visitor::FromNestedArray->new();
13
14         # given this nested array tree
15         my $array_tree = [
16                           'Root', [
17                               'Child1', [
18                                       'GrandChild1',
19                                       'GrandChild2'
20                                       ],
21                               'Child2'
22                               ]
23                           ];
24         # set the array tree we
25         # are going to convert
26         $visitor->setArrayTree($array_tree);
27
28         $tree->accept($visitor);
29
30         # this then creates the equivalent Tree::Simple object:
31         # Tree::Simple->new("Root")
32         #     ->addChildren(
33         #         Tree::Simple->new("Child1")
34         #             ->addChildren(
35         #                 Tree::Simple->new("GrandChild1"),
36         #                 Tree::Simple->new("GrandChild2")
37         #             ),
38         #         Tree::Simple->new("Child2"),
39         #     );
40

DESCRIPTION

42       Given a tree constructed from nested arrays, this Visitor will create
43       the equivalent Tree::Simple hierarchy.
44

METHODS

46       new There are no arguments to the constructor the object will be in its
47           default state. You can use the "setNodeFilter", "includTrunk" and
48           "setArrayTree" methods to customize its behavior.
49
50       includTrunk ($boolean)
51           Setting the $boolean value to true (1) will cause the node value of
52           the $tree object passed into "visit" to be set with the root value
53           found in the $array_tree. Setting it to false (0), or not setting
54           it, will result in the first value in the $array_tree creating a
55           new node level.
56
57       setNodeFilter ($filter_function)
58           This method accepts a CODE reference as its $filter_function
59           argument and throws an exception if it is not a code reference.
60           This code reference is used to filter the tree nodes as they are
61           created, the $filter_function is passed the node value extracted
62           from the array prior to it being inserted into the tree being
63           built. The $filter_function is expected to return the value desired
64           for inclusion into the tree.
65
66       setArrayTree ($array_tree)
67           This method is used to set the $array_tree that our Tree::Simple
68           hierarchy will be constructed from. It must be in the following
69           form:
70
71             [
72               'Root', [
73                   'Child1', [
74                         'GrandChild1',
75                         'GrandChild2'
76                         ],
77                   'Child2'
78                 ]
79             ]
80
81           Basically each element in the array is considered a node, unless it
82           is an array reference, in which case it is interpreted as
83           containing the children of the node created from the previous
84           element in the array.
85
86           The tree is validated prior being accepted, if it fails validation
87           an exception will be thrown. The rules are as follows;
88
89           The array tree must not be empty.
90               It makes not sense to create a tree out of nothing, so it is
91               assumed that this is a sign of something wrong.
92
93           All nodes of the array tree must not be array references.
94               The root node is validated against this in this function, but
95               all subsequent nodes are checked as the tree is built. Any
96               nodes found to be array references are rejected and an
97               exception is thrown. If you desire your node values to be array
98               references, you can use the node filtering mechanism to achieve
99               this as the node is filtered after it is validated.
100
101           The array tree must be a single rooted tree.
102               If there is a second element in the array tree, it is assumed
103               to be the children of the root, and therefore must be in the
104               form of an array reference.
105
106       visit ($tree)
107           This is the method that is used by Tree::Simple's "accept" method.
108           It can also be used on its own, it requires the $tree argument to
109           be a Tree::Simple object (or derived from a Tree::Simple object),
110           and will throw and exception otherwise.
111

BUGS

113       None that I am aware of. Of course, if you find a bug, let me know, and
114       I will be sure to fix it.
115

CODE COVERAGE

117       See the CODE COVERAGE section in Tree::Simple::VisitorFactory for more
118       information.
119

SEE ALSO

121       These Visitor classes are all subclasses of Tree::Simple::Visitor,
122       which can be found in the Tree::Simple module, you should refer to that
123       module for more information.
124

AUTHOR

126       stevan little, <stevan@iinteractive.com>
127

129       Copyright 2004, 2005 by Infinity Interactive, Inc.
130
131       <http://www.iinteractive.com>
132
133       This library is free software; you can redistribute it and/or modify it
134       under the same terms as Perl itself.
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138perl v5.30.0                      2019T-r0e7e-:2:6Simple::Visitor::FromNestedArray(3)
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