NAME

GraphViz2::Marpa::Renderer::Graphviz - A renderer for GraphViz2::Marpa-style dot files

Synopsis

See "Synopsis" in GraphViz2::Marpa.

Description

GraphViz2::Marpa::Renderer::Graphviz provides a renderer for Graphviz (dot) graph definitions parsed by GraphViz2::Marpa.

It outputs a string to the output file, which (ideally) exactly matches the graph definition input to the paser, although there might be small differences in the line-by-line formatting.

This module is the default rendering engine for GraphViz2::Marpa.

Installation

Install GraphViz2::Marpa as you would for any Perl module:

Run:

        cpanm GraphViz2::Marpa

or run:

        sudo cpan GraphViz2::Marpa

or unpack the distro, and then either:

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

or:

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

Constructor and Initialization

new() is called as my($renderer) = GraphViz2::Marpa::Renderer::Graphviz -> new(k1 => v1, k2 => v2, ...).

It returns a new object of type GraphViz2::Marpa::Renderer::Graphviz.

Key-value pairs accepted in the parameter list (see corresponding methods for details [e.g. maxlevel()]):

o logger => $logger_object

Specify a logger object.

To disable logging, just set logger to the empty string.

Default: An object of type Log::Handler.

o maxlevel => $level

This option is only used if this module creates an object of type Log::Handler. See Log::Handler::Levels.

Default: 'notice'.

o minlevel => $level

This option is only used if this module creates an object of type Log::Handler. See Log::Handler::Levels.

Default: 'error'.

No lower levels are used.

o output_file => $file_name

Specify the name of the output file to write. This will contain the text string of the rendered graph.

Default: ''.

The default means the output file is not written. Use the "output_string()" method to retrieve the string.

o tree => anObjectOfTypeTreeDAG_Node

Specify the tree tokens output by the parser.

This option is mandatory.

The tree is output from GraphViz2::Marpa.

Default: ''.

Methods

format_node($node, $opts)

$node is an object of type Tree::DAG_Node.

$opts is the same hashref of options as passed in to the call to walk_down() in run().

format_node() is called to generate a string representation of $node, using $opts.

Examine the default implementation of format_node(), above, for more details.

log($level, $s)

Calls $self -> logger -> $level($s) if ($self -> logger).

logger([$logger_object])

Here, the [] indicate an optional parameter.

Get or set the logger object.

To disable logging, just set 'logger' to the empty string (not undef), in the call to "new()".

'logger' is a parameter to "new()". See "Constructor and Initialization" for details.

maxlevel([$string])

Here, the [] indicate an optional parameter.

Get or set the value used by the logger object.

This option is only used if GraphViz2::Marpa:::Lexer or GraphViz2::Marpa::Parser create an object of type Log::Handler. See Log::Handler::Levels.

'maxlevel' is a parameter to "new()". See "Constructor and Initialization" for details.

minlevel([$string])

Here, the [] indicate an optional parameter.

Get or set the value used by the logger object.

This option is only used if GraphViz2::Marpa:::Lexer or GraphViz2::Marpa::Parser create an object of type Log::Handler. See Log::Handler::Levels.

'minlevel' is a parameter to "new()". See "Constructor and Initialization" for details.

output_file([$file_name])

Here, the [] indicate an optional parameter.

Get or set the name of the output file. This will contain the text string of the rendered graph.

If the output file name is not set, use the "output_string()" method to retrieve the string.

'output_file' is a parameter to "new()". See "Constructor and Initialization" for details.

run()

Renders the tree of parsed tokens as a string and, optionally, writes that string to the output file.

Returns 0 for success and 1 for failure.

tree()

Gets or sets the tree of tokens to be rendered.

'tree' is a parameter to "new()". See "Constructor and Initialization" for details.

FAQ

See "FAQ" in GraphViz2::Marpa.

Machine-Readable Change Log

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

Version Numbers

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

Repository

https://github.com/ronsavage/GraphViz2-Marpa

Support

Email the author, or log a bug on RT:

https://rt.cpan.org/Public/Dist/Display.html?Name=GraphViz2::Marpa.

Author

GraphViz2::Marpa was written by Ron Savage <ron@savage.net.au> in 2012.

Home page: http://savage.net.au/index.html.

Copyright

Australian copyright (c) 2012, 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/