Crate rdf_types 

The Resource Description Framework (RDF) is a very simple graph data model defined by the World Wide Web Consortium (W3C) to represent arbitrary pieces of information, primarily intended for the web. Nodes of the graph are called resources, and resources are connected together using relations, which are resources themselves.

This crate provides generic, purely semantic (as opposed to syntactic) building blocks to work with RDF data, regardless of how resources are represented:

• Triple and Quad are simple tuple types representing a triple/quad of resources (a quad additionally carries an optional named graph);
• Domain and its FiniteDomain, GenDomain and ConstGenDomain refinements abstract over a set of resources, independently of any graph or dataset;
• Graph and Dataset abstract over, respectively, a collection of triples and a collection of quads, with refinements to iterate over their triples/quads and resources, perform pattern matching, and mutate them. BTreeGraph/IndexedBTreeGraph and BTreeDataset/IndexedBTreeDataset are ready-to-use implementations backed by B-trees.

Every trait and type above is generic over the resource type, and comes with fallible (Try*) and asynchronous (Async*) counterparts, so they can be implemented on top of I/O-backed or otherwise fallible storage.

This crate does not provide any lexical or syntactic representation of RDF resources (IRIs, blank node identifiers, literals, etc.), nor the notion of interpretation mapping such lexical resources to semantic ones. See the rdf-syntax crate for that.

Modules

btree_dataset

btree_graph

diff

Diff between two RDF datasets.

indexed_btree_dataset

indexed_btree_graph

pattern

Triple/quad patterns, used to describe a set of triples/quads by leaving some of their components unspecified (variables).

util

Small iterator adapters shared by the fallible/owned trait implementations of this crate.

Structs

BTreeBijection

Blank node identifier bijection between two (isomorphic) datasets.

BTreeDataset

BTree-based RDF dataset.

BTreeGraph

BTree-based RDF graph.

IndexedBTreeDataset

Indexed BTree-based RDF dataset, optimized for pattern matching operations.

IndexedBTreeGraph

Indexed BTree-based RDF graph, optimized for pattern matching operations.

Quad

RDF quad.

QuadObjects

Iterator over the objects of a dataset matching a given graph, subject and predicate.

QuadPredicatesObjects

Iterator over the predicates of a dataset matching a given graph and subject, along with, for each predicate, the objects matching it.

StaticDomain

Trivial domain implementation that just fixes the resource type R, without tracking any actual resource.

Triple

RDF triple.

TripleObjects

Iterator over the objects of a graph matching a given subject and predicate.

TriplePredicatesObjects

Iterator over the predicates of a graph matching a given subject, along with, for each predicate, the objects matching it.

Enums

Cow

A clone-on-write smart pointer.

Traits

AsyncConstGenDomain

Domain that can spawn fresh new resources from a shared reference.

AsyncDatasetMut

Async mutable dataset.

AsyncFiniteDataset

Async finite dataset.

AsyncFiniteDomain

Asynchronous finite domain.

AsyncFiniteGraph

Async finite graph.

AsyncGenDomain

Domain that can spawn fresh new resources.

AsyncGraphMut

Async mutable graph.

AsyncPatternMatchingDataset

Async pattern-matching-capable dataset.

AsyncPatternMatchingGraph

Async pattern-matching-capable graph.

ConstGenDomain

Domain that can spawn fresh new resources from a shared reference.

Dataset

RDF dataset.

DatasetMut

Mutable dataset.

Domain

RDF resource domain.

FiniteDataset

Dataset that can be traversed using a provided quad iterator.

FiniteDomain

Finite domain.

FiniteGraph

Graph that can be traversed using a provided triple iterator.

GenDomain

Domain that can spawn fresh new resources.

Graph

RDF graph.

GraphMut

Mutable graph.

MultiPatternMatchingDataset

Multi-pattern-matching-capable dataset.

MultiPatternMatchingGraph

Multi-pattern-matching-capable graph.

NamedGraphFiniteDataset

Dataset that can enumerate the distinct resources it uses to name a graph.

ObjectFiniteDataset

Dataset that can enumerate the distinct resources it uses as an object.

ObjectFiniteGraph

Graph that can enumerate the distinct resources it uses as an object.

PatternMatchingDataset

Pattern-matching-capable dataset.

PatternMatchingDatasetMut

Pattern-matching-capable mutable dataset.

PatternMatchingGraph

Pattern-matching-capable graph.

PatternMatchingGraphMut

Pattern-matching-capable mutable graph.

PredicateFiniteDataset

Dataset that can enumerate the distinct resources it uses as a predicate.

PredicateFiniteGraph

Graph that can enumerate the distinct resources it uses as a predicate.

ResourceFiniteDataset

Dataset that can enumerate the distinct resources it mentions (in any position of any quad).

ResourceFiniteGraph

Graph that can enumerate the distinct resources it mentions (in any position of any triple).

SubjectFiniteDataset

Dataset that can enumerate the distinct resources it uses as a subject.

SubjectFiniteGraph

Graph that can enumerate the distinct resources it uses as a subject.

TryConstGenDomain

Fallible domain that can spawn fresh new resources from a shared reference.

TryDataset

Fallible dataset.

TryDatasetMut

Fallible mutable dataset.

TryDomain

Fallible domain.

TryFiniteDataset

Fallible dataset that can be traversed using a provided quad iterator.

TryFiniteDomain

Fallible finite domain.

TryFiniteGraph

Fallible graph that can be traversed using a provided triple iterator.

TryGenDomain

Fallible domain that can spawn fresh new resources.

TryGraph

Fallible graph.

TryGraphMut

Fallible mutable graph.

TryPatternMatchingDataset

Pattern-matching-capable fallible dataset.

TryPatternMatchingGraph

Pattern-matching-capable fallible graph.

Functions

are_isomorphic

Checks that there is an isomorphism between the datasets a and b.

find_bijection

Finds a blank node identifier bijection from a to b. If such bijection exists, there is an isomorphism between a and b.