NAME

XTM::AsTMa - Topic Map Parsing of AsTMa instances.

SYNOPSIS

# reading a topic map description from a file/url
$atm = new XTM::AsTMa (file => 'mymap.atm');
$tm  = $atm->sync_in();

DESCRIPTION

This package provides parsing functionality for AsTMA instances as described in the package documentation (doc directory) or at

Currently, only AsTMa= is supported, with the following constraints/additions:

no macro support

This feature was experimental and is now deprecated.

following directives are supported:

%cancel

Cancels the parse process on this very line and ignores the rest of the AsTMa instance. Useful for debugging faulty maps. There is an appropriate line written to STDERR.

%log [ message ]

Writes a line to STDERR reporting the line number and an optional message. Useful for debugging.

%name [ name ]

Adds a name attribute to the topic map.

%encoding [ encoding ]

Specifies which encoding to use to interpret the following text. This implies that this directive may appear several times to change the encoding. Whether this is a good idea in terms of information management, is a different question.

Note: It is still not allowed to use several name : encoding clauses.

Note: If no encoding is provided, utf8 is assumed.

%auto_complete [ on/off ]

Turns on/off auto completion.

Note: topics which have been mentioned in a 'is-reified-by' clause will be always generated.

A directive can be inserted anywhere in the document but must be at the start of a line.

INTERFACE

Constructor

The constructor expects a hash as parameter containing one of the following fields:

url:

If given, then the AsTMa instance will be read from this url.

file:

If given, then the AsTMa data will be read from this file (This is just a convenience function as it will be mapped to url).

text:

If given, then the AsTMa instance will be read directly from this text.

auto_complete

If set to 0, the AsTMa loader will NOT try to automatically generate topics which have been mentioned without being declared.

Note: topics which have been mentioned in a 'is-reified-by' clause will be always generated.

If several fields (file, url, text) are specified, it is undefined which one will be taken.

Examples:

   $atm = new XTM::AsTMa (file => 'here.atm');
   $atm = new XTM::AsTMa (url  => 'file:here.atm',  # the same
			  auto_complete => 0);      # but with auto_completion turned off
   $atm = new XTM::AsTMa (text => '# this is AsTMa');

Methods

last_mod

$time = $atm->last_mod

returns the UNIX time when the resource has been modified last. undef is returned if the result cannot be determined.

sync_in

$tmmemory = $atm->sync_in

loads an AsTMa instance and returns a XTM::Memory object. Note that that all undefined topics will be defined automatically, unless auto_complete is set to 0.

The only optional parameter is consistency. It will be used when building the map while reading the AsTMa instance. See XTM for details.

sync_out

is not implemented.

SEE ALSO

XTM

AUTHOR INFORMATION

Copyright 200[1-2], Robert Barta <rho@telecoma.net>, All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. http://www.perl.com/perl/misc/Artistic.html