Graph::Writer::XML - write out directed graph as XML

       Neil Bowers <neil@bowers.com>

       Copyright (c) 2001-2012, Neil Bowers. All rights reserved.  Copyright (c)  2001,  Canon  Research  Centre
       Europe. All rights reserved.

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

perl v5.32.1                                       2021-09-19                            Graph::Writer::XML(3pm)

Graph::Writer::XML is a class for writing out a directed graph in a simple XML format.  The graph must be
       an instance of the Graph class, which is actually a set of classes developed by Jarkko Hietaniemi.

       The XML format is designed to support the Graph classes: it can be used to represent a single graph with
       a collection of nodes, and edges between those nodes.  The graph, nodes, and edges can all have
       attributes specified, where an attribute is a (name,value) pair, with the value being scalar.

       Attribute values must be scalar. If they're not, well, you're on your own.

new()
       Constructor - generate a new writer instance.

           $writer = Graph::Writer::XML->new();

       This doesn't take any arguments.

   write_graph()
       Write a specific graph to a named file:

           $writer->write_graph($graph, $file);

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

       Graph::Writer::XML - write out directed graph as XML

       <https://github.com/neilb/Graph-ReadWrite>

       XML::Writer
           The perl module used to actually write out the XML.  It handles entities etc.

       Graph
           Jarkko   Hietaniemi's   modules   for   representing  directed  graphs,  available  from  CPAN  under
           modules/by-module/Graph/

       Algorithms in Perl
           The O'Reilly book which has a chapter on directed graphs, which is based around Jarkko's modules.

       Graph::Writer
           The base-class for Graph::Writer::XML

           use Graph;
           use Graph::Writer::XML;

           $graph = Graph->new();
           # add edges and nodes to the graph

           $writer = Graph::Writer::XML->new();
           $writer->write_graph($graph, 'mygraph.xml');