nb-09 solutions — From permit to duties and powers

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How to verify

Checkable against law test packs/examples/language-demo/permits (28 checked, 28 passed). Identifiers and code as written.

1. Flipping duty violated to SATISFIED and to UNDETERMINED

Answer: replace the explicit denial with the positive fact for SATISFIED; drop the denial (assert neither) for UNDETERMINED.

The violated test asserts not decision_notified(ann) past the closed window, so the achievement condition provably never held — VIOLATED. Asserting decision_notified(ann) instead (as duty satisfied does) meets the condition inside the window — SATISFIED. Asserting neither (as outcome unknown — no violation does) leaves the engine with no witness either way — UNDETERMINED. This is the trio the article’s changed condition describes: same window, same parties, three fact patterns, three states.

2. Why maintenance violation, not “unknown”

Answer: the recorded fines are a counterexample, and a counterexample is the witness maintenance needs.

A maintenance goal claims the condition holds at every point of the window. One moment where permit_eligible(ann) provably fails (here via outstanding_fines, which defeats eligibility through FinesRefusal) — refutes the universal claim, so VIOLATED. Contrast without a certificate the post-window outcome is unknown: judged 2027-01-05 with no counterexample on record, hence UNDETERMINED. Silence never violates; a counterexample always does.

3. Standing, exercise, grounds in the groundless power

Answer: standing present, exercise present, grounds absent.

Standing: permit_office(city-hall) and permit_eligible(ann) are both asserted, so the rule’s when holds and the power exists. Exercise: revocation_notice(city-hall, ann) is asserted, so the exercise act occurred. Grounds: resells_permit(ann) is nowhere asserted, so valid_when is false and the exercise operates nothing — permit_revoked stays NEITHER. Add the resale fact and nothing else, and the twin test power exercised lawfully goes TRUE_ONLY.

4. Why MayObject applies in March but not mid-April

Answer: the liberty’s window is 1–31 March 2026; a 15 April refusal falls outside it, so the position does not apply at all.

ObjectionRight fires only when permit_refused(a, o) holds, and the resulting MayObject carries window [@2026-03-01, @2026-03-31]. On 10 March a refusal is inside the window — ACTIVE. A refusal dated 15 April is outside the window the rule declares, so there is no MayObject for it: not VIOLATED, not UNDETERMINED — absent. Windows bound applicability first, outcomes second (see Limits).

How to verify

Terminal

law test packs/examples/language-demo/permits

Expected: итого: 28 проверено, 28 прошли, 0 не прошли, 0 не исполнены. The deciding tests are duty satisfied, duty violated, outcome unknown — no violation, maintenance violated by counterexample, without a certificate the post-window outcome is unknown, power exercised lawfully, power without grounds does not operate, and liberty and immunity.