NAME
Attean::API::Model - RDF Model
VERSION
This document describes Attean::API::Model version 0.012
DESCRIPTION
The Attean::API::Model role defines a common API for all RDF models to conform to. It is provides a consistent interface for probing, counting, and retrieving Attean::API::Quads matching a pattern, as well as related functionality such as enumerating the graph names, and extracting structured data from the models' quads.
REQUIRED METHODS
The following methods are required by the Attean::API::Model role:
get_quads( $subject, $predicate, $object, $graph )-
Returns an Attean::API::Iterator for quads in the model that match the supplied
$subject,$predicate,$object, and$graph.Any of these terms may be:
* An Attean::API::Term object, in which case matching is equality-based
* A Attean::API::Variable object or
undef, in which case that term will be considered as a wildcard for the purposes of matching* An ARRAY reference of Attean::API::Term objects, in which case the matching will be equality-based on the disjunction of the supplied terms
The returned iterator conforms to both Attean::API::Iterator and Attean::API::QuadIterator.
count_quads( $subject, $predicate, $object, $graph )-
Returns the number of quads in the model matching the supplied pattern (using the same matching semantics as
get_quads). get_graphs-
Returns an Attean::API::Iterator of distinct Attean::API::Term objects that are used in the graph position of quads in the model.
METHODS
The Attean::API::Model role provides default implementations of the following methods:
get_bindings( $subject, $predicate, $object, $graph )-
Returns an Attean::API::Iterator of Attean::API::Result objects corresponding to quads in the model matching the supplied pattern. For each Attean::API::Variable in the pattern list, a mapping will be present in the corresponding result object. For example,
$model->get_bindings( variable('s') )will return an iterator of results containing just a mapping from's'to subjects of all quads in the model. get_list( $graph, $head )-
Returns an Attean::API::Iterator of Attean::API::Term objects that are members of the rdf:List with the specified
$head(and matching restricted to only the specified$graph). get_sequence( $graph, $head )-
Returns an Attean::API::Iterator of Attean::API::Term objects that are members of the rdf:Sequence with the specified
$head(and matching restricted to only the specified$graph). subjects( $predicate, $object, $graph )-
Returns an Attean::API::Iterator of Attean::API::Term objects of all subjects of quads matching the supplied pattern (using the same matching semantics as
get_quads). predicates( $subject, $object, $graph )-
Returns an Attean::API::Iterator of Attean::API::Term objects of all predicates of quads matching the supplied pattern (using the same matching semantics as
get_quadswith anundefpredicate). objects( $subject, $predicate, $graph )-
Returns an Attean::API::Iterator of Attean::API::Term objects of all objects of quads matching the supplied pattern (using the same matching semantics as
get_quadswith anundefobject). graphs( $subject, $predicate, $object )-
Returns an Attean::API::Iterator of Attean::API::Term objects of all graphs of quads matching the supplied pattern (using the same matching semantics as
get_quadswith anundefgraph). graph_nodes( $graph )-
Returns an Attean::API::Iterator of Attean::API::Term objects of unique subjects and objects present in the specified
$graph.
BUGS
Please report any bugs or feature requests to through the GitHub web interface at https://github.com/kasei/attean/issues.
SEE ALSO
AUTHOR
Gregory Todd Williams <gwilliams@cpan.org>
COPYRIGHT
Copyright (c) 2014--2016 Gregory Todd Williams. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.