nb-01 solutions — First permit: facts, a rule and a question

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Exercise (article section 10)Checkable test

Exercise (article section 10)

Setup: vehicle_registered(ann) asserted, resident(ann) not asserted. Question: status of truth(permit_eligible(ann)) under the probe program.

Answer

NEITHER. The strict rule needs both conditions; with resident(ann) missing it does not fire, and nothing else supports or denies permit_eligible(ann) — symmetric to the resident-without-car case in the article. This is unknown, not a refusal (full story in nb-02).

Checkable test

Append to /tmp/nb01-probe/probe.lawtest (probe program unchanged):

Arxo Law

test "car without residency is unknown" {
    given {
        context { legal_time @2026-03-01; decision_time @2026-03-01T09:00:00Z; knowledge_time @2026-03-01T09:00:00Z; timezone "UTC"; }
        assert "vehicle-ann": vehicle_registered(entity_ref("urn:demo:probe:ann")) { origin case_input; }
    }
    evaluate truth(permit_eligible(entity_ref("urn:demo:probe:ann")));
    expect truth_status == NEITHER;
}

Command:

Terminal

law engine test /tmp/nb01-probe/probe.lawtest --program /tmp/nb01-probe/probe.law

Observed result (2026-10-02, with the article’s two base tests present):

Output

test PASS: resident with a car is eligible
test PASS: resident without a car is unknown
test PASS: car without residency is unknown

(A fourth probe test, asserting the conclusion fires no rule, fails as designed — applied(urn:demo:probe#PermitEligibility): в документе нет — demonstrating the article’s typical-mistake section.)