The Standard Premise Library
Translated from the canonical Japanese page stdlib/README.md. The
source_shaabove records the source revision; a consistency check flags this page when the Japanese original changes.
Commentary on the transparent standard premises bundled with Kairos. Transparent = not
language built-in magic: they are written in the same primitive-definition / derived-definition
syntax a user can write (../spec/20-premise-layer.md), so their contents can be read and swapped
out.
The language specification (../spec/) explains syntax and semantics and cites the standard
premises only as “examples”; the exhaustive contents of each premise (definition, each word,
scope) are this directory’s charge.
Runnable examples ( ``kairos ` fences plus # eval: / #=>) are verified in full by the
reference implementation under the same doctest conventions as reference/ (the canonical text of
the conventions is ../reference/README.md).
Contents
- Gregorian — the Gregorian calendar (a primitive-definition root). day/weekday/month/year/quarter, the public boundary words, the calendar-coordinate sugar (yearNo/monthNo/dayNo), the dependency direction (bottom-up; leap is a value), the separation of weekday and WKST, and scope.
- Fiscal — the fiscal calendar (April start). The one-line
yearderivation, automatic tracking via mechanism A, fiscal-year numbering and fiscal month numbers, the variants (the US federal type, half-years) and what is out of reach. Bundled with the language (usable with no declaration). - ISOWeek — the ISO 8601 week calendar. The isoWeek/isoYear windows and the
projections of week number, day-of-week, and ISO year. The equivalent transformation that stands
on settled vocabulary alone, with no
label:attachment expression (the F40 reduction), and its wkst independence. Bundled with the language. - Kyureki (Japanese — data-heavy, not mirrored) — the Kyureki, the old Japanese lunisolar calendar. A data-dependent calendar system that cuts months at new-moon data (the NAOJ calendar bulletins 2025–2027, leap sixth month included), with the projections of Kyureki dates and rokuyō. Being a premise carrying data, it is not bundled (a worked instance of provenance governance = ADR-26).
Future candidates
- The Japanese era calendar (era-name labels) and the like, as primitive / derived definitions.