NAME

TM::Bulk - Topic Maps, Bulk Retrieval Trait

SYNOPSIS

  my $tm = .....                          # get a map from anywhere

  use TM::Bulk;
  use Class::Trait;
  Class::Trait->apply ($tm, 'TM::Bulk');  # give the map the trait

  # find out environment of topic
  my $vortex = $tm->vortex ('some-lid',
                           {
                            'types'       => [ 'types' ],
                            'instances'   => [ 'instances*', 0, 20 ],
                            'topic'       => [ 'topic' ],
                            'roles'       => [ 'roles',     0, 10 ],
                            'members'     => [ 'players' ],
                           },
                           );
  # find names of topics (optionally using a scope preference list)
  my $names = $tm->names ([ 'ccc', 'bbb', 'aaa' ], [ 's1', 's3', '*' ]);

DESCRIPTION

Especially when you build user interfaces, you might need access to a lot of topic-related information. Instead of collecting this 'by foot' the following methods help you achieve this more effectively.

names

$name_hash_ref = $tm->names ($lid_list_ref, [ $scope_list_ref ] )

This method takes a list (reference) of topic ids and an optional list of scoping topic ids. For the former it will try to find the names (topic names for TMDM acolytes).

If the list of scopes is empty then the preference is on the unconstrained scope. If no name for a topic is in that scope, some other will be used.

If the list of scopes is non-empty, it directs to look first for a name in the first scoping topic, then second, and so on. If you want to have one name in any case, append * to the scoping list.

If no name exist for a particular lid, then an undef is returned in the result hash. References to non-existing topics are ignored.

The overall result is a hash (reference). The keys are of the form topic-id @ scope-id (without the blanks) and the name strings are the values.

vortex

$info = $tm->vortex (, $vortex_lid, $what_hashref, $scope_list_ref )

This method returns a lot of information about a particular toplet (vortex). The function expects the following parameters:

lid:

the lid of the toplet in question

what:

a hash reference describing the extent of the information (see below)

scopes:

a list (reference) to scopes (currently NOT honored)

To control what exactly should be returned, the what hash reference can contain following components. All of them being tagged with <n,m> accept an additional pair of integer specify the range which should be returned. To ask for the first twenty, use 0,19, for the next 20,39. The order in which the identifiers is returned is undefined but stable over subsequent read-only calls.

topic:

fetches the toplet (which is only the subject locator, subject indicators information).

names (<n,m>):

fetches all names (as array reference triple [ type, scope, string value ])

occurrences (<n,m>):

fetches all occurrences (as array reference triple [ type, scope, value ])

instances (<n,m>):

fetches all toplets which are direct instances of the vortex (that is regarded as class here);

instances* (<n,m>):

same as instances, but including all instances of subclasses of the vortex

types (<n,m>):

fetches all (direct) types of the vortex (that is regarded as instance here)

types* (<n,m>):

fetches all (direct and indirect) types of the vortex (that is regarded as instance here)

subclasses (<n,m>):

fetches all direct subclasses

subclasses* (<n,m>):

same as subclasses, but creates reflexive, transitive closure

superclasses (<n,m>):

fetches all direct superclasses

superclasses* (<n,m>):

same as superclasses, but creates reflexive, transitive closure

roles (<n,m>):

fetches all assertion ids where the vortex plays a role

peers (<n,m>):

fetches all topics which are also a direct instance of any of the (direct) types of this topic

peers* (<n,m>):

fetches all topics which are also a (direct or indirect) instances of any of the (direct) types of this topic

peers** (<n,m>):

fetches all topics which are also a (direct or indirect) instances of any of the (direct or indirect) types of this topic

The function will determine all of the requested information and will prepare a hash reference storing each information into a hash component. Under which name this information is stored, the caller can determine with the hash above as the example shows:

Example:

  $vortex = $tm->vortex ('some-lid',
                         {
                          'types'       => [ 'types' ],
                          'instances'   => [ 'instances*', 0, 20 ],
                          'topic'       => [ 'topic' ],
                          'roles'       => [ 'roles',     0, 10 ],
                         },
                        );

The method dies if lid does not identify a proper toplet.

SEE ALSO

TM::Overview

COPYRIGHT AND LICENSE

Copyright 200[3-57] by Robert Barta, <drrho@cpan.org>

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