Author image Dorian Taylor
and 1 contributors


RDF::KV::Patch - Representation of RDF statements to be added or removed


Version 0.06


    my $patch = RDF::KV::Patch->new;

    $patch->add_this($s, $p, $o, $g);
    $patch->remove_this($s, $p, undef, $g); # a wildcard

    $patch->apply($model); # an RDF::Trine::Model instance


This module is designed to represent a diff for RDF graphs. You add statements to its add or remove sides, then you "apply" them to a RDF::Trine::Model object. This should probably be part of RDF::Trine if there isn't something like this in there already.



Stub constructor, nothing of interest.

add_this { $S, $P, $O | $statement } [, $graph ]

Add a statement, or set of terms, to the add side of the patch.

This method and its siblings are fairly robust, and can take a wide variety of inputs, from triple and quad statements, to individual subject/predicate/object/graph objects, to string literals, to variable nodes, to undef. They are processed by the following scheme:

dont_add_this { $S, $P, $O | $statement } [, $graph ]

Remove a statement, or set of terms, from the add side of the patch.

remove_this { $S, $P, $O | $statement } [, $graph ]

Add a statement, or set of terms, to the remove side of the patch.

dont_remove_this { $S, $P, $O | $statement } [, $graph ]

Remove a statement, or set of terms, from the remove side of the patch.

apply { $model | $remove, $add }

Apply the patch to an RDF::Trine::Model object. Statements are removed first, then added. Transactions (i.e. "begin_bulk_ops" in RDF::Trine::Model) are your responsibility.

Alternatively, supply the remove and add functions directly:

  sub _remove_or_add {
    my ($subject, $predicate, $object, $graph) = @_;

    # do stuff ...

    # return value is ignored

Inputs will be either RDF::Trine::Node objects, or undef, in the case of remove.




Copyright 2013 Dorian Taylor.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.