Tree::Simple::Visitor::LoadClassHierarchy(3) A Visitor for loading class hierarchies into a Tree::Simple hierarchy


use Tree::Simple::Visitor::LoadClassHierarchy;
# create an visitor
my $visitor = Tree::Simple::Visitor::LoadClassHierarchy->new();
# set class as an instance, or
# as a package name
# pass our visitor to the tree
# the $tree now mirrors the inheritance hierarchy of the $class


This visitor will traverse a class's inheritance hierarchy (through the @ISA arrays) and create a Tree::Simple hierarchy which mirrors it.


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.
includeTrunk ($boolean)
Setting the $boolean value to true (1) will cause the node value of the $tree object passed into "visit" to be set with the root value found in the class hierarchy. Setting it to false (0), or not setting it, will result in the first value in the class hierarchy creating a new node level.
includeMethods ($boolean)
Setting the $boolean value to true (1) will cause methods to be added as a children of the class node. Setting it to false (0), or not setting it, will result in this not happening.

NOTE: Methods are sorted ascii-betically before they are added to the tree. This allows a more predictable hierarchy.

setClass ($class)
The argument $class should be either a class name or an instance, it is then used as the root from which to determine the class hierarchy.
setNodeFilter ($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 created, the $filter_function is passed the node value extracted from the hash prior to it being inserted into the tree being built. The $filter_function is expected to return the value desired for inclusion into the tree.
visit ($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.

The $tree argument which is passed to "visit" must be a leaf node. This is because this Visitor will create all the sub-nodes for this tree. If the tree is not a leaf, an exception is thrown. We do not require the tree to be a root though, and this Visitor will not affect any nodes above the $tree argument.


Improve the "includeMethods" functionality
I am not sure the tree this creates is the optimal tree for this situation. It is sufficient for now, until I have more of an actual need for this functionality.
Add "includeFullSymbolTable" functionality
This would traverse the full symbol tables and produce a detailed tree of everything it finds. This takes a lot more work, and as I have no current need for it, it remains in the TO DO list.


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


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


stevan little, <[email protected]>


Copyright 2004, 2005 by Infinity Interactive, Inc.


This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.