# NAME
[GraphViz2::Parse::ISA](https://metacpan.org/pod/GraphViz2::Parse::ISA) - Visualize N Perl class hierarchies as a graph
# SYNOPSIS
use strict;
use warnings;
use File::Spec;
use GraphViz2::Parse::ISA;
my $parser = GraphViz2::Parse::ISA->new;
unshift @INC, 't/lib';
$parser->add(class => 'Adult::Child::Grandchild', ignore => []);
$parser->add(class => 'HybridVariety', ignore => []);
$parser->generate_graph;
my $format = shift || 'svg';
my $output_file = shift || "parse.code.$format";
$parser->graph->run(format => $format, output_file => $output_file);
See scripts/parse.isa.pl.
# DESCRIPTION
Takes a class name and converts its class hierarchy into a graph. This can be done for N different classes before the graph is generated.
You can write the result in any format supported by [Graphviz](http://www.graphviz.org/).
# Constructor and Initialization
## Calling new()
`new()` is called as `my($obj) = GraphViz2::Parse::ISA->new(k1 => v1, k2 => v2, ...)`.
It returns a new object of type `GraphViz2::Parse::ISA`.
Key-value pairs accepted in the parameter list:
- o graph => $graphviz\_object
This option specifies the GraphViz2 object to use. This allows you to configure it as desired.
The default is GraphViz2->new. The default attributes are the same as
in the synopsis, above.
The default for [GraphViz2::Parse::ISA](https://metacpan.org/pod/GraphViz2::Parse::ISA) is to plot from the bottom to
the top (Grandchild to Parent). This is the opposite of [GraphViz2](https://metacpan.org/pod/GraphViz2).
This key is optional.
# METHODS
## add(class => $class\[, ignore => $ignore\])
Adds the class hierarchy of $class to an internal structure.
$class is the name of the class whose parents are to be found.
$ignore is an optional arrayref of class names to ignore. The value of $ignore is _not_ preserved between calls to add().
After all desired calls to add(), you _must_ call ["generate\_graph()"](#generate_graph) to actually trigger the call to the [GraphViz2](https://metacpan.org/pod/GraphViz2) methods add\_node() and add\_edge().
Returns $self for method chaining.
See scripts/parse.isa.pl.
## generate\_graph()
Processes the internal structure mentioned under add() to add all the nodes and edges to the graph.
After that you call [GraphViz2](https://metacpan.org/pod/GraphViz2)'s run() method on the graph object. See ["graph()"](#graph).
Returns $self for method chaining.
See scripts/parse.isa.pl.
## graph()
Returns the graph object, either the one supplied to new() or the one created during the call to new().
# Scripts Shipped with this Module
## scripts/parse.isa.pl
Demonstrates combining 2 Perl class hierarchies on the same graph.
Outputs to ./html/parse.isa.svg by default. Change this by providing a
format argument (e.g. `svg`) and a filename argument.
# THANKS
Many thanks are due to the people who chose to make [Graphviz](http://www.graphviz.org/) Open Source.
And thanks to [Leon Brocard](http://search.cpan.org/~lbrocard/), who wrote [GraphViz](https://metacpan.org/pod/GraphViz), and kindly gave me co-maint of the module.
The code in add() was adapted from [GraphViz::ISA::Multi](https://metacpan.org/pod/GraphViz::ISA::Multi) by Marcus Thiesen, but that code gobbled up package declarations
in comments and POD, so I used [Pod::Simple](https://metacpan.org/pod/Pod::Simple) to give me just the source code.
# AUTHOR
[GraphViz2](https://metacpan.org/pod/GraphViz2) was written by Ron Savage _<ron@savage.net.au>_ in 2011.
Home page: [http://savage.net.au/index.html](http://savage.net.au/index.html).
# COPYRIGHT
Australian copyright (c) 2011, Ron Savage.
All Programs of mine are 'OSI Certified Open Source Software';
you can redistribute them and/or modify them under the terms of
The Perl License, a copy of which is available at:
http://dev.perl.org/licenses/