Feature support

Legend: ✅ supported · ⚠️ partial / gated · ❌ unsupported.

SHACL Core

Feature	Status	Notes
Node & property shapes	✅
Targets — targetNode, targetClass, targetSubjectsOf, targetObjectsOf, implicit class	✅
Cardinality — minCount, maxCount	✅
Value type — datatype, nodeKind, class	✅
Range — min/maxInclusive, min/maxExclusive	✅	numeric, date/time, and duration ordering
String — minLength, maxLength, pattern (+ flags), languageIn, uniqueLang	✅
Logical — and, or, not, xone	✅
Shape-based — node, property, qualifiedValueShape (+ counts, qualifiedValueShapesDisjoint)	✅
Property pairs — equals, disjoint, lessThan, lessThanOrEquals	✅	on node and property shapes
Other — closed (+ ignoredProperties), hasValue, in	✅
Paths — predicate, inverse, sequence, alternative, zeroOrMore, oneOrMore, zeroOrOne	✅
severity, deactivated, message	✅

SHACL-AF (Advanced Features)

Feature	Status	Notes
Rules — sh:TripleRule, sh:SPARQLRule (CONSTRUCT)	✅	forward-chained to a fixed point with sh:order / sh:condition
Node expressions — sh:this, constants, sh:path, sh:filterShape, sh:intersection, sh:union, function application	✅
SPARQL targets — sh:target + sh:select	✅
SPARQL constraints — sh:sparql (sh:select / sh:ask)	✅	native execution with Spareval fallback
Custom constraint components — sh:parameter + sh:validator / sh:nodeValidator / sh:propertyValidator	✅	optional params, simple & complex $PATH; report path
Expression constraints — sh:expression	✅
SHACL functions — sh:SPARQLFunction in node expressions	✅	full data-graph access
SHACL functions — sh:SPARQLFunction called from SPARQL (sh:sparql, CONSTRUCT, dash:expression)	⚠️	evaluated as pure functions of their arguments; a body that reads the data graph is gated (see below)
JavaScript — sh:js*, sh:JSFunction	❌	no JS engine

Recursion & semantics

Feature	Status	Notes
Stratified recursive shapes	✅	gfp validation / lfp inference per stratum
Non-stratifiable schemas (cycle through negation)	❌	diagnosed and refused, never guessed

Feature-handling policy

Partially supported features are handled per an on_unsupported setting (EngineOptions in Rust; the on_unsupported= keyword on validate / validate_algebra / infer and PreparedValidator in Python):

• "ignore" (default) — best-effort: e.g. a graph-reading function called from a SPARQL context is evaluated over an empty dataset (result may be unreliable).

• "error" — fail loudly: the unsupported construct is refused so the failure surfaces (e.g. as a constraint error) instead of a silent wrong answer.

conforms, report, text = shifty.validate(data, shapes, on_unsupported="error")