rdf_triple.pl -- Create triples from intermediate representation

Convert the output of xml_to_rdf/3 from library(rdf) into a list of triples of the format described below. The intermediate representation should be regarded a proprietary representation.

rdf(Subject, Predicate, Object).

Where `Subject' is

Atom: The subject is a resource
each(URI): URI is the URI of an RDF Bag
prefix(Pattern): Pattern is the prefix of a fully qualified Subject URI

And `Predicate' is

Atom: The predicate is always a resource

And `Object' is

Atom: URI of Object resource
literal(Value): Literal value (Either a single atom or parsed XML data)

rdf_triples(+Term, -Triples) is det

rdf_triples(+Term, -Tridpples, +Tail) is det

Convert an object as parsed by rdf.pl into a list of rdf/3 triples. The identifier of the main object created is returned by rdf_triples/3.

Input is the `content' of the RDF element in the format as generated by load_structure(File, Term, [dialect(xmlns)]). rdf_triples/3 can process both individual descriptions as well as the entire content-list of an RDF element. The first mode is suitable when using library(sgml) in `call-back' mode.

triples(-Triples, -Id, +In, -Tail)[private]

DGC set processing the output of xml_to_rdf/3. Id is unified to the identifier of the main description.

property(Property, N, NN, Subject)// is det[private]

Generate triples for {Subject, Pred, Object}. Also generates triples for Object if necessary.

Arguments:

Property

- One of

Pred = Object: Used for normal statements
id(Id, Pred=Object): Used for reified statements

statement(+Subject, +Pred, +Object, +Id, +BagH, -BagT)[private]

Add a statement to the model. If nonvar(Id), we reinify the statement using the given Id.

li_pred(+Pred, -Pred, +Nth, -NextNth)[private]

Transform rdf:li predicates into _1, _2, etc.

collection(+Elems, -Id)[private]

Handle the elements of a collection and return the identifier for the whole collection in Id.

rdf_start_file(+Options, -Cleanup) is det

Initialise for the translation of a file.

rdf_end_file(:Cleanup) is det

Cleanup reaching the end of an RDF file.

anon_prefix(-Prefix) is semidet

If defined, it is the prefix used to generate a blank node.

rdf_reset_ids is det

Utility predicate to reset the gensym counters for the various generated identifiers. This simplifies debugging and matching output with the stored desired output (see rdf_test.pl).