Expand description
The Resource Description Framework (RDF) is a powerful method for modeling data and knowledge defined by the World Wide Web Consortium (W3C). A RDF dataset consists in a collection of graphs connecting nodes, values and predicates. This crate provides traits and implementations of Generalized RDF (gRDF) where nodes, values and predicates have the same representation.
Note that this crates requires rust compiler version 1.65 or later. It needs Generic Associated Typed (GAT) to work properly.
Basic usage
Exploring a dataset
Each Dataset
implementation provides many iterators to explore the data.
One simple way is to iterate through the quad of the dataset:
for Quad(subject, predicate, object, graph) in dataset {
// do something
}
Another way is to access each graph individually using Dataset::graph
.
For a given graph, it is then possible to iterate through the triples of the
graph:
let graph = dataset.graph(id).unwrap();
for Triple(subject, predicate, object) in graph {
// do something
}
It is also possible to explore the graph logically, subject by subject, predicate by predicate, object by object:
// for each subject of the graph...
for (subject, predicates) in graph.subjects() {
// for each predicate it is subject...
for (predicate, objects) in predicates {
// for each triple (subject, predicate, object)...
for object in objects {
// do something
}
}
}
Inserting new data
Insertion can be done on MutableDataset
implementations using
MutableDataset::insert
:
let mut dataset: HashDataset<Term> = HashDataset::new();
dataset.insert(Quad(subject, predicate, object, graph));
Again it is possible to access each graph of the dataset mutably:
let mut graph = dataset.graph_mut(id).unwrap();
graph.insert(Triple(subject, predicate, object));
Custom RDF types
The types used to represent RDF subjects, predicate and objects are
parameters of the dataset. Anything can be used although they default to the
rdf_types::Term
type that represents generic RDF nodes (blank nodes,
IRI-named nodes and literal values).
Modules
- Dataset implementation based on
BTreeMap
andBTreeSet
. - Dataset implementation based on
HashMap
andHashSet
.
Macros
Structs
- Graph implementation based on
BTreeMap
andBTreeSet
. - View a graph from the perspective of a single subject resource.
- Graph implementation based on
HashMap
andHashSet
. - Simple
GraphAccess
implementation for graphs such thatSubject = Object
. - RDF quad.
- RDF triple.
- View a dateset from the perspective of a single graph subject resource.
Traits
- gRDF dataset.
- Specifies how to access a dataset and reinterpret triples subjects as graph labels.
- gRDF graph.
- Specifies how to access a graph and reinterpret triples objects as subjects.
- Mutable dataset.
- Mutable gRDF graph.
- Sized gRDF dataset that can be converted into iterators.
- Sized gRDF graph that can be converted into iterators.