Data::Grove::Parent − provide parent properties to
Data::Grove objects

 use Data::Grove::Parent;

      $root = $object‐>root;
 $rootpath = $object‐>rootpath;
 $tied = $object‐>add_magic([ $parent ]);

      $node = Data::Grove::Parent‐>new($hash [, $parent]);
 $node_list = Data::Grove::ParentList‐>new($array [, $parent]);

Data::Grove::Parent is an extension to Data::Grove that adds
‘"Parent"’ and ‘"Raw"’ properties to Data::Grove objects and
methods for returning the root node of a grove, a list of
nodes between and including the root node and the current
node, and a method that creates parented nodes.

     Data::Grove::Parent works by creating a Perl ‘‘tied’’
object that contains a parent reference (‘"Parent"’) and a
reference to the original Data::Grove object (‘"Raw"’).
Tying‐magic is used so that every time you reference the
Data::Grove::Parent object it actually references the
underlying raw object.

     When you retrieve a list or a property of the Raw
object, Data::Grove::Parent automatically adds magic to the
returned list or node.  This means you only call
‘add_magic()’ once to create the first Data::Grove::Parent
object and then use the grove objects like you normally

     The most obvious use of this is so you don’t have to
call a ‘"delete"’ method when you want to release a grove or
part of a grove; since Data::Grove and Data::Grove::Parent
objects have no cyclic references, Perl can garbage collect
them normally.

     A secondary use is to allow you to reuse grove or
property set fragments in multiple trees.  WARNING:
Data::Grove currently does not protect you from creating
your own cyclic references!  This could lead to infinite
loops if you don’t take care to avoid them.


    ‘"root()"’ returns the root node if ‘$object’ is a
    ‘"Data::Grove::Parent"’ object.  ‘"rootpath()"’ returns
    an array of all the nodes between and including the root
    node and ‘$object’.


$tied = $object−>add_magic([ $parent ])
    ‘"add_magic()"’ returns a "Data::Grove::Parent" object
    with ‘$object’ as it’s ‘"Raw"’ object.  If ‘$parent’ is
    given, that becomes the tied object’s parent object.

Ken MacLeod,

perl(1), Data::Grove(3)