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graphviz::parse::recdescent(3pm) [debian man page]

GraphViz::Parse::RecDescent(3pm)			User Contributed Perl Documentation			  GraphViz::Parse::RecDescent(3pm)

NAME

       GraphViz::Parse::RecDescent - Visualise grammars

SYNOPSIS

	 use GraphViz::Parse::RecDescent;

	 # Either pass in the grammar
	 my $graph = GraphViz::Parse::RecDescent->new($grammar);
	 print $g->as_png;

	 # or a Parse::RecDescent parser object
	 my $graph = GraphViz::Parse::RecDescent->new($parser);
	 print $g->as_ps;

DESCRIPTION

       This module makes it easy to visualise Parse::RecDescent grammars.  Writing Parse::RecDescent grammars is tricky at the best of times, and
       grammars almost always evolve in ways unforseen at the start. This module aims to visualise a grammar as a graph in order to make the
       structure clear and aid in understanding the grammar.

       Rules are represented as nodes, which have their name on the left of the node and their productions on the right of the node. The subrules
       present in the productions are represented by edges to the subrule nodes.

       Thus, every node (rule) should be connected to the graph - otherwise a rule is not part of the grammar.

       This uses the GraphViz module to draw the graph. Thanks to Damian Conway for the idea.

       Note that the Parse::RecDescent module should be installed.

METHODS

   new
       This is the constructor. It takes one mandatory argument, which can either be the grammar text or a Parse::RecDescent parser object of the
       grammar to be visualised. A GraphViz object is returned.

	 # Either pass in the grammar
	 my $graph = GraphViz::Parse::RecDescent->new($grammar);

	 # or a Parse::RecDescent parser object
	 my $graph = GraphViz::Parse::RecDescent->new($parser);

   as_*
       The grammar can be visualised in a number of different graphical formats. Methods include as_ps, as_hpgl, as_pcl, as_mif, as_pic, as_gd,
       as_gd2, as_gif, as_jpeg, as_png, as_wbmp, as_ismap, as_imap, as_vrml, as_vtx, as_mp, as_fig, as_svg. See the GraphViz documentation for
       more information. The two most common methods are:

	 # Print out a PNG-format file
	 print $g->as_png;

	 # Print out a PostScript-format file
	 print $g->as_ps;

BUGS

       Translating the grammar to a graph is accomplished by peeking inside the internals of a parser object, which is a tad scary. A new version
       of Parse::RecDescent with different internals may break this module.

       At the moment, almost all Parse::RecDescent directives are supported. If you find one that has been missed - let me know!

       Unfortunately, alternations (such as the following) do not produce very pretty graphs, due to the fact that they are implicit (unamed)
       rules and are implemented by new long-named subrules.

	 character: 'the' ( good | bad | ugly ) /dude/

       Hopefully Parse::FastDescent will make this all much easier.

AUTHOR

       Leon Brocard <acme@astray.com>

COPYRIGHT

       Copyright (C) 2001, Leon Brocard

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

perl v5.14.2							    2012-04-02					  GraphViz::Parse::RecDescent(3pm)

Check Out this Related Man Page

GraphViz::Regex(3pm)					User Contributed Perl Documentation				      GraphViz::Regex(3pm)

NAME

       GraphViz::Regex - Visualise a regular expression

SYNOPSIS

	 use GraphViz::Regex;

	 my $regex = '(([abcd0-9])|(foo))';

	 my $graph = GraphViz::Regex->new($regex);
	 print $graph->as_png;

DESCRIPTION

       This module attempts to visualise a Perl regular expression. Understanding regular expressions is tricky at the best of times, and regexess
       almost always evolve in ways unforseen at the start. This module aims to visualise a regex as a graph in order to make the structure clear
       and aid in understanding the regex.

       The graph visualises how the Perl regular expression engine attempts to match the regex. Simple text matches or character classes are
       represented by.box-shaped nodes. Alternations are represented by a diamond-shaped node which points to the alternations. Repetitions are
       represented by self-edges with a label of the repetition type (the nodes being repeated are pointed to be a full edge, a dotted edge points
       to what to match after the repetition). Matched patterns (such as $1, $2, etc.) are represented by a 'START $1' .. 'END $1' node pair.

       This uses the GraphViz module to draw the graph.

METHODS

   new
       This is the constructor. It takes one mandatory argument, which is a string of the regular expression to be visualised. A GraphViz object
       is returned.

	 my $graph = GraphViz::Regex->new($regex);

   as_*
       The regex can be visualised in a number of different graphical formats. Methods include as_ps, as_hpgl, as_pcl, as_mif, as_pic, as_gd,
       as_gd2, as_gif, as_jpeg, as_png, as_wbmp, as_ismap, as_imap, as_vrml, as_vtx, as_mp, as_fig, as_svg. See the GraphViz documentation for
       more information. The two most common methods are:

	 # Print out a PNG-format file
	 print $g->as_png;

	 # Print out a PostScript-format file
	 print $g->as_ps;

BUGS

       Note that this module relies on debugging information provided by Perl, and is known to fail on at least two versions of Perl: 5.005_03 and
       5.7.1. Sorry about that - please use a more recent version of Perl if you want to use this module.

AUTHOR

       Leon Brocard <acme@astray.com>

COPYRIGHT

       Copyright (C) 2000-1, Leon Brocard

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

perl v5.14.2							    2012-04-02						      GraphViz::Regex(3pm)
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