NAME

TM - Perl extension for TmTk

SYNOPSIS

use TM;

$tm = TM::TopicMap->new();
$tm->load_file("/opt/maps/mymap.xtm","xtm_simple","xml");
$t = $tm->get_topic("IS13250::UniqueName","RoleBaseName");
$val = $tm->get_property($t,"IS13250::UniqueName");
$tm->dump();
$tm->require("SAM");

DESCRIPTION

TM - Perl extension for TmTk, the Topic Maps Toolkit. TmTk is available at Gooseworks.org [http://www.gooseworks.org].

Creating A Topic Map

$tm = TM::TopicMap->new();

Creates a new TopicMap object.

Loading A Topic Map from a file

In order to load a topic map document into your TopicMap, you need to tell the internal parsing component, where the document is found, what processing model to apply to it and also, what parser to invoke:

$tm->load_file("/opt/maps/mymap.xtm","xtm_simple","xml") or die("unable to load topic map,",$tm->get_error());

Available rpocessing models are:

xtm_simple
rdf_common
iso2788

Available parse modes are:

xml
rdfxml
lines

You can load maps at any time and all loaded maps will be merged.

Loading A Topic Map from a string

If you have your topic map in a string and not in a file, use

  $tm->load_string(
	qq{<topicMap>
	   <topic id="t1" />
	   </topicMap>},
	"xtm_simple","xml") or
                die("unable to load topic map,",$tm->get_error());

A method for loading a topic map in chunks is planned for the next release.

Loading a Topic Map Application (TMA)

Sometimes it is desired to load additional TMAs (ones that have not been loaded by the applied processing model(s) implicitly). To do this, you simply call the require() method and supply it the name of the TMA:

$tm->require("MYTMA") or die("cannot load MYTMA, " . $tm->get_error());

Using the Topic Map Views

TmTk provides a special way of querying a topic map, that is called parameterized views. A view is a conceptual abstraction of a subset of the semantics of a (or a combination of) TMA. Examples for views are "Index", "Taxonomy", or "RolePlayings".

The process of querying a topic map with TmTk is almost identical to event-oriented parsing of an XML document: Together with the actual query you pass a start-event- and an end-event callback function to the query method of a topic map object. The topic map object will call these callbacks according to certain events in the view processing.

  $tm = TM::TopicMap->new;


  sub topic_start
  {
	my ($ud, $name, $href) = @_;
	#print " start $name\n";
	if( $name eq "topic" )
	{
		my $hr = {};
		
		$hr->{topic} = $href->{topic};
		$hr->{indicators} = $href->{indicators};
		$hr->{names} = [];
		
		$$ud->{last_topic} = $hr;
	}
	if( $name eq "basename" )
	{
		push(@{$$ud->{last_topic}->{names}}, $href->{string});

	}
  }
  sub topic_end
  {
	my ($ud,$name) = @_;
	#print " end $name\n";
	if( $name eq "topic" )
	{
		my $hr = $$ud->{last_topic};
		print "Topic: $hr->{topic}\n";
		foreach(@{$hr->{indicators}})
		{
			print "  $_\n";
		}
		foreach(@{$hr->{names}})
		{
			print "  $_\n";
		}
		print "\n\n";
	}
  }

  $tm->query(\$user_data, \&topic_start, \&topic_end, "VIEW topic(topic=200)" );

That;s all

AUTHOR

Jan Algermissen algermissen@acm.org