RDF::SKOS - SKOS - Simple Knowledge Organization System
use RDF::SKOS; my $skos = new RDF::SKOS; # adding one $skos->concept ('aaa' => { prefLabels => [ [ 'xxx', 'de' ] ] }); # regain it my $c = $skos->concept ('aaa'); # get all of them my @cs = $skos->concepts; # label stuff @labels = $c->prefLabels; @labels = $c->altLabels; @labels = $c->hiddenLabels; @labels = $c->notes; @labels = $c->scopeNotes; @labels = $c->definitions; @labels = $c->examples; @labels = $c->historyNotes; @labels = $c->editorialNotes; @labels = $c->changeNotes; # broader/narrower @cs = $c->narrower @cs = $c->narrowerTransitive @cs = $c->broader @cs = $c->broaderTransitive # associated @cs = $c->related @cs = $c->relatedTransitive # get all schemes @ss = $skos->schemes # get a particular $sch = $skos->scheme ('some_scheme'); # find top-level concepts @tops = $skos->topConcepts ('some_scheme');
!!! DEVELOPER RELEASE (THERE MAY BE DRAGONS) !!!
!!! PLEASE SEE THE README FOR LIMITATIONS !!!
SKOS is a model for expressing very basic concept schemes, much simpler than Topic Maps or RDF. This includes subject headings, taxonomies, folksonomies. For a primer see
This package suite supports SKOS in that:
It provides packages with particular SKOS data,
It implements SKOS on top of various RDF stores, so that you can read RDF and enjoy an SKOS view on top of that,
Or you can derive your own subclasses of the generic RDF::SKOS, especially for the case where you have a different format.
This implementation assumes that each concept has a unique ID. That is simply a scalar.
Following things are not yet added:
At the moment there is mostly read-only support. You can add concepts to the SKOS, but there is no proper interface for added/removing concepts, or schemes.
There is also no support for collections yet.
And none for all *Match relationships between concepts.
And most of the SKOS constraints are not yet honored.
If you need any of that, please throw obscene amounts of (good) chocolate into my direction. Or write a patch! No. Better send chocolate.
The constructor does not expect any additional information.
Example:
my $skos = new RDF::SKOS;
$c = $skos->concept ('xyz')
Given the ID of the concept, this method returns an RDF::SKOS::Concept object representing the concept. If there is no such concept undef will be returned.
undef
If - apart from the ID - another parameter is added, that must be a HASH reference carrying all the attributes for that concept. That concept will be stored under this ID. If there was already something there, it will be overwritten.
@concepts = $skos->concepts
This method return a list of RDF::SKOS::Concept objects, each for a concept in the SKOS.
@schemes = $skos->schemes
This will return a list of RDF::SKOS::Scheme objects which all represent one scheme within the SKOS.
$scheme = $skos->scheme (ID)
Returns the scheme object for the one with that ID.
@tops = $skos->topConcepts ('scheme_a')
Given the ID of a concept scheme, this will return a list of RDF::SKOS::Concept objects representing the top-level concepts in that scheme.
All these methods expect the concept ID to be passed in as the sole parameter:
@labels = $skos->prefLabels ('some-concept')
Out comes a list of tuples. Each tuple contains first the value, then the language tag, both as scalars.
Returns the list of preferred labels.
Returns the list of alternative labels.
Returns the list of hidden labels.
Returns the list of notes.
NOTE: No property subclassing is honored, so scopeNotes are NOT included (yet).
Returns the list of scope notes.
Returns the list of definitions.
Returns the list of examples.
Returns the list of history notes.
Returns the list of editorial notes.
Returns the list of change notes.
$cs = $skos->narrower ($ID)
$cs = $skos->narrowerTransitive ($ID)
$cs = $skos->broader ($ID)
$cs = $skos->broaderTransitive ($ID)
This method expects the ID of a concept and returns a list of RDF::SKOS::Concept objects which have a narrower relationship to that with ID. As the semantics of narrower involves that it is the inverse of broader also these relationships are respected.
narrower
If you want narrower/broader to be interpreted transitively, then use the variant narrowerTransitive. That not only interprets everything transitively, it also picks up the narrowTransitive relationships inside the SKOS object.
narrowerTransitive
NOTE: I understand that this deviates somewhat from the standard. But it makes life easier.
See above
This method expects the ID of a concept and returns a list of RDF::SKOS::Concept objects which have a related relationship to that identified with ID. Note that related is always symmetric, not not automatically transitive. If you want transitivity to be honored, then use the variant relatedTransitive.
related
relatedTransitive
NOTE: This interpretation is fully SKOS compliant.
Robert Barta, <drrho at cpan.org>
<drrho at cpan.org>
Please report any bugs or feature requests to bug-rdf-skos at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=RDF-SKOS. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.
bug-rdf-skos at rt.cpan.org
Copyright 2009 Robert Barta, all rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
To install RDF::SKOS, copy and paste the appropriate command in to your terminal.
cpanm
cpanm RDF::SKOS
CPAN shell
perl -MCPAN -e shell install RDF::SKOS
For more information on module installation, please visit the detailed CPAN module installation guide.