Querying

Query only after a successful solve(). Membership, enumeration and explanations answer different questions; a negative membership answer is not an API error. See Querying for their meaning.

Ground queries

query(predicate, terms) returns a boolean using the typed terms described in Runtime EDB. It can find query-authorized EDB, policy and derived facts. An unknown symbol returns false without interning. Invalid predicates, permissions or arity remain native errors, never a fabricated false.

const allowed: boolean = pg.query('allow', ['alice'])

Enumerating derived IDB facts

enumerate(predicate, arity) returns resolved and copied rows:

const rows: (string | bigint | boolean)[][] = pg.enumerate('event_result', 4)

It enumerates only derived IDB facts of the authorized predicate. No native symbol ID, pointer or borrowed view escapes. Display integers with String(); plain JSON.stringify cannot serialize bigint.

Why-true explanations

explainTrue(predicate, terms) returns the canonical engine text. It returns status=not-derived if there is no derived witness, including when a query found an EDB or policy fact. A truncated document remains a successfully returned, explicitly bounded document. Unknown symbols raise NOT_FOUND.

Why-false explanations

explainFalse(predicate, terms) explains absence when the terms are known. A present fact gives status=not-applicable. An unknown symbol gives NOT_FOUND, even though the corresponding query returns false. status=truncated means the search was incomplete; it is not a complete proof of non-derivability. Both explanations are requested explicitly; the playground computes them only when their disclosure is opened.

const present = pg.query('allow', ['alice'])
const explanation = present
  ? pg.explainTrue('allow', ['alice'])
  : pg.explainFalse('allow', ['alice'])

The explanation is text; inspect its document and status fields rather than treating its mere presence as authorization.