Crate shifty_engine 

Validation + SHACL-AF inference execution (Layers 3, 6, 7).

Layer 3 lives here: the naive denotational evaluator that is the conformance oracle — relational path evaluation (path), value-type checks (value), and shape/schema satisfaction (validate). The rule/fixpoint inference engine (Layer 6) and compiled executors (Layer 7) come later; every execution mode must agree with this oracle.

validate owns semantic satisfaction and is the correctness oracle. [mod@infer] owns least-fixpoint rule execution over a mutable context. frozen, the private native executor, and private SPARQL façade form the indexed/read-only fast path used after inference. evidence and witness turn oracle conclusions into source-oriented coverage and repair-oriented derivations. synthesize, enumerate, and gate keep repair construction, choice, and validation of a proposed edit separate.

Public APIs expose shallow operations; the caches and semantic translations that make them fast and correct remain in their owning modules.

Reusable document sessions

CompiledShapes::compile admits a loaded shapes document once and retains its authored schema, normalized schema, function definitions, and rule schedule. Cloning the handle shares those resources. A physical validation plan is built lazily, so inference-only sessions do not pay for it.

Create an EvaluationSession with CompiledShapes::session, choosing SessionData::Separate or SessionData::Embedded and fixed SessionOptions for inference, graph mode, and engine policy. In Separate mode, Data evaluates data alone, Union also reads shapes, and UnionAll also selects focus nodes from shapes. Embedded mode evaluates the evolving data graph. Every mode binds the authored shapes source as the named $shapesGraph, including after inference. SessionOptions::default uses Union mode, disables inference, and ignores unsupported features. FindingOptions::default selects all entry shapes, considers all severities, and sorts findings.

A session owns an immutable asserted-data snapshot. Inference runs at construction; the frozen index is built on the first validation, report, or evidence operation. EvaluationSession::with_delta edits asserted data and creates a new session, recomputing inference under the same policy. The original session and its results remain valid. A selected evidence pair belongs to exactly one session; passing it to another session’s explain returns EvaluationError::ForeignPair.

Compilation diagnostics are available from CompiledShapes::diagnostics and inference diagnostics from EvaluationSession::diagnostics. Strict unsupported-feature policy can reject session construction. Conformance scans count logical failures, while finding-based validation applies its selected minimum severity; their conforms values can therefore differ.

CompiledShapes is Send + Sync and may be shared across workers. Sessions retain operation-local Rc/RefCell executor state and should be created separately on each worker.

Re-exports

pub use compact::CompactError;

pub use compact::Sharing;

pub use compact::compact;

pub use compact::compact_value;

pub use compact::expand;

pub use compact::expand_value;

pub use compact::expand_with_catalog;

pub use compact::sharing;

pub use compact::to_compact_json;

pub use enumerate::EnumOptions;

pub use enumerate::FixpointResult;

pub use enumerate::RepairSolution;

pub use enumerate::candidates;

pub use enumerate::enumerate_repair;

pub use enumerate::repair_to_fixpoint;

pub use evidence::ConformanceOptions;

pub use evidence::ConformanceRun;

pub use evidence::PreparedEvidenceValidator;

pub use evidence::SelectedPair;

pub use evidence::validate_graphs_with_evidence;

pub use evidence::validate_graphs_with_evidence_and_mode;

pub use evidence::validate_graphs_with_evidence_and_mode_and_options;

pub use evidence::validate_with_context_and_evidence;

pub use evidence::validate_with_context_and_evidence_and_options;

pub use evidence::validate_with_evidence;

pub use evidence::validate_with_evidence_and_options;

pub use gate::RepairOutcome;

pub use gate::apply;

pub use gate::gate;

pub use report::PropertyWitness;

pub use report::ValidationReport;

pub use report::ValidationResult;

pub use report::evaluate_function_expression;

pub use report::property_witnesses_graphs_with_mode;

pub use report::property_witnesses_graphs_with_mode_and_options;

pub use report::report_to_graph;

pub use report::validate_report;

pub use report::validate_report_graphs;

pub use report::validate_report_graphs_with_mode;

pub use report::validate_report_graphs_with_mode_and_options;

pub use report::validate_report_with_options;

pub use sharing::ResultSharing;

pub use sharing::result_sharing;

pub use synthesize::EvidenceOrigin;

pub use synthesize::SynthesizedRepair;

pub use synthesize::synthesize;

pub use synthesize::synthesize_focus;

pub use synthesize::synthesize_focus_with_origins;

pub use synthesize::synthesize_with_origins;

pub use validate::EngineOptions;

pub use validate::NonStratifiable;

pub use validate::Reason;

pub use validate::UnsupportedPolicy;

pub use validate::ValidationGraphMode;

pub use validate::ValidationOptions;

pub use validate::ValidationOutcome;

pub use validate::Violation;

pub use validate::focus_nodes;

pub use validate::graph_union;

pub use validate::validate;

pub use validate::validate_graphs;

pub use validate::validate_graphs_with_mode;

pub use validate::validate_graphs_with_mode_and_options;

pub use validate::validate_plan;

pub use validate::validate_plan_graphs;

pub use validate::validate_plan_graphs_with_mode;

pub use validate::validate_plan_graphs_with_mode_and_options;

pub use validate::validate_plan_with_context;

pub use validate::validate_plan_with_context_and_options;

pub use validate::validate_plan_with_options;

pub use validate::validate_with_context;

pub use validate::validate_with_context_and_options;

pub use validate::validate_with_options;

pub use witness::BlockReason;

pub use witness::ChildEvaluation;

pub use witness::ConstraintCatalog;

pub use witness::ConstraintRecord;

pub use witness::EvaluationProgress;

pub use witness::EvaluationStatus;

pub use witness::Evidence;

pub use witness::EvidenceKind;

pub use witness::EvidenceNodeRef;

pub use witness::EvidenceRun;

pub use witness::EvidenceSummary;

pub use witness::Failure;

pub use witness::FocusEvaluation;

pub use witness::FocusSat;

pub use witness::FocusWitness;

pub use witness::MissingObligation;

pub use witness::PathSupport;

pub use witness::QualifiedMatch;

pub use witness::RejectedCandidate;

pub use witness::RelKind;

pub use witness::SatTrace;

pub use witness::Satisfaction;

pub use witness::StatementEvaluation;

pub use witness::Witness;

pub use witness::satisfy_shape;

pub use witness::shape_id_for_iri;

pub use witness::witness_node;

pub use witness::witness_shape;

pub use witness::witness_violations;

Modules

compact

Compact, lossless encoding of an EvidenceRun.

enumerate

The enumeration reference driver (docs/07-repair-drivers.md §4) and the candidates helper (docs/06-repair.md §3.3).

evidence

Unified evidence-carrying validation.

frozen

Dictionary-encoded RDF dataset shared by inference’s native and fallback evaluators. A committed inference batch updates its indexes before the next rule group reads them. Validation selects its own default-graph view over the final inference snapshot without rebuilding the dataset.

gate

The re-validation gate (docs/06-repair.md §8).

path

Relational evaluation of the path algebra ⟦π⟧^G (doc 00 §2, Table 1).

profile

Opt-in execution telemetry (doc §269). Collected via a thread-local so no validation API signatures change. Enable with enable(), consume with take().

report

W3C sh:ValidationReport generation (component-granular, RDF-driven).

sharing

How much an EvidenceRun shares across independently addressable validation results.

synthesize

Synthesis: FocusWitness → RepairTree (docs/06-repair.md §6).

validate

Reference shape satisfaction G, v ⊨ φ and schema validation G ⊨ S (doc 00 §3–§4, Table 2). This is the conformance oracle: the optimized engines in later layers must agree with it.

value

Evaluation of value types test(τ) and the term ordering used by sh:lessThan, ranges, etc. Naive reference semantics.

witness

The witnessing evaluator (docs/06-repair.md §5) — the structured, lossless sibling of explain. For a focus node that fails a statement it returns a Failure: the failed sub-DAG of φ, pruned to exactly what did not hold, with the structural gap at each node. Its dual, Satisfaction, records why a shape currently holds, so a Not(φ) failure can be repaired by breaking φ. One dispatcher produces both tagged polarities; they are mutually recursive only in their data grammar through Not.

Structs

CompiledShapes

A shapes document compiled once for use with many data snapshots.

EvaluationSession

EvidenceOptions

ExecutionDiagnostic

FindingOptions

SessionOptions

SparqlDiagnostic

Debugging detail for one SPARQL-backed constraint evaluation (sh:sparql or a custom SPARQL-based constraint component), meant to be attached to a violating report result so a failure is never a dead end: it shows exactly what query ran, what it was bound to, and what rows it actually returned.

Enums

CompileError

EvaluationError

Only explain and explain_canonical can fail: every other evaluation on a constructed session is total, so those return their value directly.

SessionData

SessionError