Neil Bowers


Graph::Reader::Dot - class for reading a Graph instance from Dot format


    use Graph::Reader::Dot;
    use Graph;

    $reader = Graph::Reader::Dot->new();
    $graph = $reader->read_graph('');


Graph::Reader::Dot is a class for reading in a directed graph in the file format used by the dot tool (part of the AT+T graphviz package).

Graph::Reader::Dot is a subclass of Graph::Reader, which defines the generic interface for Graph reader classes.



Constructor - generate a new reader instance.

    $reader = Graph::Reader::Dot->new();

This doesn't take any arguments.


Read a graph from a file:

    $graph = $reader->read_graph( $file );

The $file argument can be either a filename or a filehandle of a previously opened file.


Controls, if implicit node attributes given by the dot directive node[] will be merged into (new) nodes. Setting it to 0 or undef (default) will not disable this feature. Setting it to any other value will enable this feature.


Controls, if implicit edge attributes given by the dot directive edge[] will be merged into edges. Setting it to 0 or undef (default) will not disable this feature. Setting it to any other value will enable this feature.


  • Default (graph) attributes in subgraphs (i.e. inside {}) are not processed.

  • Sub nodes as used by dot's record node shape are supported.

  • Undirected graphs will be treated as directed graphs. This means that the -- edge operator works as the -> edge operator.

  • Be aware that you are loosing scope information on writing back the graph.

  • Multiple node[] or edge[] statements in the same scope are not correctly supported.


The home page for the AT+T graphviz toolkit that includes the dot tool.


The base class for Graph::Reader::Dot.


Used to serialise a Graph instance in Dot format.


Jarkko Hietaniemi's classes for representing directed graphs.


Another base class for Graph::Reader::Dot. The Parse::Yapp module comes with the following copyright notice:

The Parse::Yapp module and its related modules and shell scripts are copyright (c) 1998-1999 Francois Desarmenien, France. All rights reserved.

You may use and distribute them under the terms of either the GNU General Public License or the Artistic License, as specified in the Perl README file.

If you use the "standalone parser" option so people don't need to install Parse::Yapp on their systems in order to run you software, this copyright noticed should be included in your software copyright too, and the copyright notice in the embedded driver should be left untouched.


Mark A. Hillebrand <>


Copyright (c) 2001 by Mark A. Hillebrand. All rights reserved.

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