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Pin a multi-year calendar

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# Pin a multi-year calendar

## Intention

I want to use one unchanging calendar set over the whole declared period.

## Incorrect form and why it stays silent

The node period and the set digest are different obligations. An old file cannot be extended under the former hash. The timezone-database pin must be a string:

```text title="Incorrect form"
timezone_db 42;
```

Omitting timezone_db is currently accepted by check; that is not proof that the set is fit for execution.

## Correct form

```law
language "law.core" version "0.2";
package recipes.e.r09 version "0.1.0";
namespace "urn:recipe:e-time:09";

source SyntheticCalendar { kind standard; jurisdiction "none"; number "E-CALENDAR"; }
calendar Calendar {
    timezone "Asia/Almaty";
    timezone_db "iana-tzdb@2026a";
    period [@2024-01-01, @2028-01-01);
    source SyntheticCalendar;
    resource "resources/calendar-2024-2027.json";
    format "law.calendar/0.1";
    content_hash "sha256:dfd0181e1347cc2fd48b5fd81d27f3551cabae10eaefbf8b4dffb70bcbb3cd12";
}
deadline policy Days {
    start_count next_day;
    include_end true;
    roll next_working_day;
}
relation marker();
```

## Frozen execution scene



| Facts / cut | Question | Answer |
|---|---|---|
| 2024-01-05 + 1 business day | date | 2024-01-08 |
| 2027-12-30 + 1 business day | date | 2027-12-31 |
| 2027-12-31 + 1 business day | date | RUNTIME_ERROR, CALENDAR_OUT_OF_RANGE |

```law
test "early year rolls forward" {
    given {
        context {
            legal_time @2026-03-10;
            decision_time @2027-12-31T09:00:00+05:00;
            knowledge_time @2027-12-31T09:00:00+05:00;
            timezone "Asia/Almaty";
            deadline_policy Days;
        }

    }
    evaluate add_business_days(@2024-01-05, 1 business_day);
    expect value == @2024-01-08;
}
```

```law
test "late year rolls forward" {
    given {
        context {
            legal_time @2026-03-10;
            decision_time @2027-12-31T09:00:00+05:00;
            knowledge_time @2027-12-31T09:00:00+05:00;
            timezone "Asia/Almaty";
            deadline_policy Days;
        }

    }
    evaluate add_business_days(@2027-12-30, 1 business_day);
    expect value == @2027-12-31;
}
```

```law
test "beyond coverage errors" {
    given {
        context {
            legal_time @2026-03-10;
            decision_time @2027-12-31T09:00:00+05:00;
            knowledge_time @2027-12-31T09:00:00+05:00;
            timezone "Asia/Almaty";
            deadline_policy Days;
        }

    }
    evaluate add_business_days(@2027-12-31, 1 business_day);
    expect evaluation_status == RUNTIME_ERROR;
    expect issue(CALENDAR_OUT_OF_RANGE);
}
```

The calendar is synthetic: Mon–Fri, 9 March 2026 is a conventional non-working day; this is not an official calendar.

## Counterfactual

teaches substitutes a number for timezone_db and requires E1305. The set bytes and the generated law.lock are verified separately, as is rejection of both resolution chains after the resource is corrupted.

## Boundary

The set covers 2024–2027 in full; the node window is the same. This is a teaching calendar without official holidays and without a historical model of timezone transitions. Extending the period needs a new resource and a conscious update of all pins; other lock files are not rewritten.

## Pitfall

Two calendars without a chosen axis are not resolved by the first node. The resource digest and the node are pinned separately.