nb-18 solutions — Vocabulary and package composition

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Checkable against law test packs/examples/language-demo/composition (10 checked, 10 passed), law engine check packs/examples/language-demo/composition (check OK), law fix imports ./packs/examples/language-demo/composition (canonical), the frozen exhibits packs/examples/language-demo/composition/evidence/ev-use-self.txt (E1116) and evidence/ev-private.txt (E1105), and the scratch replays below (copies under /tmp, repo suite untouched). Tool law 0.1.0, language 0.2, semantics law.core/0.2, std 0.2.0. Identifiers and code as written.

1. counter_ready without the exported facts

Answer: NEITHER. The resident half holds; the counter half has no support, so the conjunction never fires.

CounterReady needs both resident(a) (vocabulary, asserted in the test’s given) and counter_open(c) (composition, fed only by CounterFacts). Remove the facts group on a scratch copy and the first suite test fails exactly this way: truth_status == TRUE_ONLY: в документе NEITHER, suite 9 прошли, 1 не прошли, exit 1 — every other test still ok. The export is load-bearing, not decorative: without it the counter side of the conjunction is silence, and silence is NEITHER, not false.

2. The desk assert written twice

Answer: nothing changes — shift_ok() stays TRUE_ONLY, suite stays 10/10.

Executed on a scratch copy with the shift_posted(open) assert doubled under two ids: 10 проверено, 10 прошли, 0 не прошли. Asserts feed a set of facts, not a multiset of derivations: the second identical assert adds no new ground, ShiftOk fires once, and the status is unchanged. If duplication changed answers, CounterFacts-style package facts plus a same-content given would double-fire everywhere — the suite shows they do not.

3. Applicant declared, resident_seen left out

Answer: still refused. The next diagnostic quotes `resident_seen`.

Executed on a scratch copy (Applicant added to the use self block, probe rule kept): law test fails the whole run with LDC-E1116, this time `resident_seen` объявлена в файле ... package.law и не заявлена в `use self` файла ... desk.law (@27:10). The block rule is one gap at a time and fail-fast for the whole run: each fix only promotes the next undeclared name into the diagnostic. Declare both and the probe builds (at which point the rule is ordinary package logic again).

4. Consumer probe over the pub relation

Answer: builds clean — and fires as soon as its premise holds.

Executed: the scratch consumer rewritten over demo.northbridge.composition::resident_seen (same manifest, same world) builds with no E1105, and with demo.northbridge.vocabulary::resident(ann) asserted in its given the probe evaluates TRUE_ONLY (1 проверено, 1 прошли). What makes it fire is the cross-package chain working end to end: vocabulary fact → composition’s ResidentSeen → resident_seen(a) → consumer’s ProbeHit. Visibility is the only gate: pub names compose across packages, the private note does not, and nothing else about the rule had to change.

5. months: "12" — text where an integer belongs

Answer: TYPE_ERROR, same as the missing field — suite exits nonzero.

Executed on a scratch copy: the record test FAILs with truth_status == TRUE_ONLY: в документе NEITHER and evaluation_status == COMPUTED: в документе TYPE_ERROR (9 прошли, 1 не прошли, exit 1) — byte for byte the same shape as the dropped-field mistake in the article. The field is declared months: Integer, so a Text literal is ill-typed at evaluation: the assert contributes no usable Slip, the rule never opens. Of the three candidates, only the two loud ones occur here, and both fail the suite — silent NEITHER with COMPUTED is reserved for well-typed absences (short slip, busy desk, missing role), never for ill-typed literals.