NAME

       TM::PSI - Topic Maps, PSI (published subject identifiers)

DESCRIPTION

       This package provides predefined subjects, all of which will be preloaded in every map
       which is instantiated with the TM package hierarchy. When the subjects are defined also
       their relationship are kept here (example: isa is an instance of an assertion).

       Every such subject is defined by its

       item identifier
           The internal identifier, which does not really mean much.

       subject identifier
           The subject indicator(s), which is ultimately the one which identifies any of the
           subjects here.

       NOTE: For none of the subjects declared here a subject address exists. All concepts are
       TM-related concepts.

       The subjects are sorted:

       TMRM-related
           These are the minimal subjects which make a map what it is. Examples are "isa" and its
           related role (type) "class" and "instance", and "is-subclass-of" and its related
           roles.

       TMDM-related (XTM things)
           These are the additional concepts which are mandated by TMDM.

       AsTMa-related
           Here are more concepts which are needed by the AsTMa= language(s), such as "template"
           or "ontology".

       TMQL-related
           Here are more concepts which are needed by TMQL.

       To learn about these predefined concepts, you can do one of the following

          use TM::PSI;
          warn Dumper ($TM::PSI::core, $TM::PSI::topicmaps_inc, $TM::PSI::astma_inc, $TM::PSI::tmql_inc);

   Taxonometry
       Two association types are predefined by the standard(s): "is-subclass-of" and "isa".
       Together with these roles are defined "subclass", "superclass" and "instance", "class",
       respectively.

       The TM::* suite of packages has these not only built in, but also works under the
       assumption that these association types and also the roles CANNOT be subclassed
       themselves. This means that no map is allowed to use, say, "is-specialization-of" as a
       subclass of "is-subclass-of".  The costs of this constraint is quite small compared to the
       performance benefits.

   Infrastructure Concepts
       To make the whole machinery work, every topic map must contain infrastructure topics such
       as "name", "occurrence" etc. They are topics like the topics a user may put into the map.
       While this is the right thing to do, in practical situation you often will want to filter
       out these infrastructure topics.  You can always get a list of these via

       @@@ fix docu @@@@@

           $tm->mids (keys %{$TM::PSI::topicmaps->{mid2iid}});

SEE ALSO

       TM

AUTHOR INFORMATION

       Copyright 200[1-68], Robert Barta <drrho@cpan.org>, 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