Crate owl_structural_model 

owl-structural-model

Typed OWL 2 structural values for Rust.

owl-structural-model is a small, dependency-light model for representing the structural values of OWL 2: entities, class expressions, literals, annotations, axioms, ontology identity, and structural patches. It is intended for parsers, editors, validators, serializers, and storage adapters that need typed OWL values without taking a dependency on an RDF store or a reasoner.

The target standard is OWL 2, the current version of the W3C Web Ontology Language. This crate models a deliberately small, currently supported subset of the OWL 2 structural specification; it is not an OWL 2 parser, reasoner, or full conformance implementation, and it does not model the older OWL 1 API.

W3C specifications

• OWL 2 Web Ontology Language Document Overview
• OWL 2 Structural Specification and Functional-Style Syntax
• OWL 2 Mapping to RDF Graphs

What it provides

The crate keeps the structural layer explicit:

• Entity and EntityKind represent OWL declarations.
• ClassExpression and ObjectPropertyExpression represent nested OWL expressions.
• OwlLiteral, Annotation, and AxiomAnnotations preserve typed values.
• Axiom represents the currently supported structural axiom forms.
• OntologyId represents anonymous, named, and versioned ontology identity.
• OntologyPatch represents a non-empty set of changes to one ontology.

It does not parse files, perform I/O, access a graph store, run a reasoner, or choose an application-specific profile. A caller can stream a document as individual axioms and retain only the bounded structural values it needs.

Example

use iri_rfc3987::Iri;
use owl_structural_model::{Axiom, ClassExpression, Entity};

fn iri(value: &str) -> Iri<String> {
    Iri::parse(value).expect("example IRI is valid").into()
}

let customer = Entity::class(iri("https://example.org/Customer"));
let declaration = Axiom::declaration(customer);
let subclass = Axiom::sub_class_of(
    ClassExpression::named(iri("https://example.org/Customer")),
    ClassExpression::named(iri("https://example.org/Party")),
);

assert!(matches!(declaration, Axiom::Declaration { .. }));
assert!(matches!(subclass, Axiom::SubClassOf { .. }));

Validation

Constructors reject invalid structural shapes immediately. For example, equivalent classes require at least two operands and language-tagged literals require a non-empty language tag. Errors are returned as the typed StructuralModelError enum.

Scope and memory

The crate models individual structural values and explicit, caller-owned patches. It does not promise that an entire ontology fits in memory. A parser or application handling an unbounded source should stream axioms and apply its own explicit limits or persistence strategy.

License

Licensed under either of:

• Apache License, Version 2.0
• MIT License

at your option. Typed OWL 2 structural values without an RDF-store dependency.

Structs

Annotation

An OWL annotation.

AxiomAnnotations

Axiom annotations attached to one structural axiom.

Entity

An OWL entity declaration target.

OntologyId

OWL ontology identity: optional ontology IRI plus optional version IRI.

OntologyPatch

A non-empty collection of structural changes for one ontology identity.

Enums

AnnotationSubject

Subject of an OWL annotation assertion.

AnnotationValue

A value that can appear in an OWL annotation.

Axiom

An OWL structural axiom.

ClassExpression

An OWL class expression.

EntityKind

Kind of OWL entity.

ObjectPropertyExpression

An OWL object property expression.

OntologyPatchOperation

One structural ontology patch operation.

OwlLiteral

A literal value used in OWL structural annotations and axioms.

StructuralModelError

A structural value failed an invariant at construction time.

Type Aliases

OntologyIdentity

Alias emphasizing that this value is metadata rather than a document.