Quick Navigator

Search Site

Unix VPS
A - Starter
B - Basic
C - Preferred
D - Commercial
MPS - Dedicated
Previous VPSs
* Sign Up! *

Contact Us
Online Help
Domain Status
Man Pages

Virtual Servers

Topology Map

Server Agreement
Year 2038

USA Flag



Man Pages

Manual Reference Pages  -  GRAPHVIZ2::PARSE::RECDESCENT (3)

.ds Aq ’


GraphViz2::Parse::RecDescent - Visualize a Parse::RecDescent grammar as a graph



        #!/usr/bin/env perl

        use strict;
        use warnings;

        use File::Spec;

        use GraphViz2;
        use GraphViz2::Parse::RecDescent;

        use Log::Handler;

        use Parse::RecDescent;

        use File::Slurp; # For read_file().

        # ------------------------------------------------

        my($logger) = Log::Handler -> new;

        $logger -> add
                 screen =>
                         maxlevel       => debug,
                         message_layout => %m,
                         minlevel       => error,

        my($graph) = GraphViz2 -> new
                 edge   => {color => grey},
                 global => {directed => 1},
                 graph  => {rankdir => TB},
                 logger => $logger,
                 node   => {color => blue, shape => oval},
        my($g)      = GraphViz2::Parse::RecDescent -> new(graph => $graph);
        my $grammar = read_file(File::Spec -> catfile(t, sample.recdescent.1.dat) );
        my($parser) = Parse::RecDescent -> new($grammar);

        $g -> create(name => Grammar, grammar => $parser);

        my($format)      = shift || svg;
        my($output_file) = shift || File::Spec -> catfile(html, "parse.recdescent.$format");

        $graph -> run(format => $format, output_file => $output_file);

See scripts/ (Scripts Shipped with this Module in GraphViz2).


Takes a Parse::RecDescent grammar and converts it into a graph.

You can write the result in any format supported by Graphviz <>.

Here is the list of output formats <>.


This module is available as a Unix-style distro (*.tgz).

See <> for help on unpacking and installing distros.


Install GraphViz2 as you would for any Perl module:


        cpanm GraphViz2

or run:

        sudo cpan GraphViz2

or unpack the distro, and then either:

        perl Build.PL
        ./Build test
        sudo ./Build install


        perl Makefile.PL
        make (or dmake or nmake)
        make test
        make install

Constructor and Initialization

Calling new()

new() is called as my($obj) = GraphViz2::Parse::RecDescent -> new(k1 => v1, k2 => v2, ...).

It returns a new object of type GraphViz2::Parse::RecDescent.

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, except for the logger of course, which defaults to ’’.

This key is optional.


create(name => CW$name, grammar => CW$grammar)

Creates the graph, which is accessible via the graph() method, or via the graph object you passed to new().

Returns $self for method chaining.

$name is the string which will be placed in the root node of the tree.

$grammar is either a Parse::RecDescent object or a grammar. If it’s a grammar, the code will fabricate an object of type Parse::RecDescent.


Returns the graph object, either the one supplied to new() or the one created during the call to new().


See FAQ in GraphViz2 and Scripts Shipped with this Module in GraphViz2.


Many thanks are due to the people who chose to make Graphviz <> Open Source.

And thanks to Leon Brocard <>, who wrote GraphViz, and kindly gave me co-maint of the module.

Version Numbers

Version numbers < 1.00 represent development versions. From 1.00 up, they are production versions.

Machine-Readable Change Log

The file Changes was converted into Changelog.ini by Module::Metadata::Changes.


Email the author, or log a bug on RT:



GraphViz2 was written by Ron Savage <> in 2011.

Home page: <>.


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 Artistic License, a copy of which is available at:

Search for    or go to Top of page |  Section 3 |  Main Index

perl v5.20.3 GRAPHVIZ2::PARSE::RECDESCENT (3) 2015-10-11

Powered by GSP Visit the GSP FreeBSD Man Page Interface.
Output converted with manServer 1.07.