Allow modules to define namespaces for RDF mappings.
Many common namespace prefixes are defined in rdf_rdf_namespaces(). However, if a module implements hook_rdf_mapping() and uses a prefix that is not defined in rdf_rdf_namespaces(), this hook should be used to define the new namespace prefix.
An associative array of namespaces where the key is the namespace prefix and the value is the namespace URI.
Note: this list is generated by pattern matching, so it may include some functions that are not actually implementations of this hook.
function hook_rdf_namespaces() {
return array(
'content' => 'http://purl.org/rss/1.0/modules/content/',
'dc' => 'http://purl.org/dc/terms/',
'foaf' => 'http://xmlns.com/foaf/0.1/',
'og' => 'http://ogp.me/ns#',
'rdfs' => 'http://www.w3.org/2000/01/rdf-schema#',
'sioc' => 'http://rdfs.org/sioc/ns#',
'sioct' => 'http://rdfs.org/sioc/types#',
'skos' => 'http://www.w3.org/2004/02/skos/core#',
'xsd' => 'http://www.w3.org/2001/XMLSchema#',
);
}