nb-20 solutions — Sources, time, and outside data

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Checkable against a scratch copy of packs/examples/language-demo/sourcetime carrying the patch below (the repo package itself stays untouched: 20 checked, 20 passed). Identifiers and code as written. Verified with law 0.1.0, law.core/0.2, on 2026-10-03.

Quiet hours as article 2b

Three places change, in this order — bytes, hashes, delta:

1. Append to sources/northbridge-overnight-2026-en.txt, after the article 2a line, separated by a blank line:

Output

Article 2b. Quiet hours (2026). Quiet hours are 23:00 to 07:00.

2. New fragment in the 2026 English edition (before PARKING_2026_ART2A_EN):

Arxo Law

fragment PARKING_2026_ART2B_EN in ORD_2026_EN {
    kind article;
    locator "article/2b";
    label en unofficial "Article 2b. Quiet hours (2026, training text)";
    text en unofficial """Quiet hours are 23:00 to 07:00.""";
    content_hash "sha256:93fadfb3a9415c960921f26f1501f7cb440a838bdb3d0b5e4fcb3d68d80c30a8";
}

The hash is sha256 of exactly Quiet hours are 23:00 to 07:00. — no trailing newline. The sentence must occur verbatim in the file, or E5202 fires even with the right hash.

3. New operation at the end of Statute2025To2026 (after the 2a insert, same effective — different locator, so no E5403):

Arxo Law

    op insert {
        locator "article/2b";
        language en;
        text """Quiet hours are 23:00 to 07:00.""";
        effective @2026-06-01;
    }

4. The longer file changes the publication hash. Recompute over the file bytes and replace the content_hash of ORD_2026_EN_TEXT:

Output

sha256:e09c9aabb1493be9e5574092e3a60e92aa5550a65e6307cb1cfc17a8da5e99ab

Skip step 4 and law engine check answers LDC-E5204 ... не дают объявленный content_hash — the chain bytes → publication → fragment → operation has four links, and the checker walks all of them.

Expected consolidate listing (exit 0):

Output

article/2 (en)
article/2a (en)
article/2b (en)

Expected diff-editions against ORD_2025 (exit 0):

Output

~ article/2 (en)
+ article/2a (en)
+ article/2b (en)
- article/1 (en)

The repealed article 1 stays gone; the two June inserts share one date and apply in author order.