Module dates 

VAPP-190: calendar-day maths, the Rust twin of packages/exponential-ui/src/dates.ts, shared by the records query (time buckets, host::query) and the bind-time expressions (Q2: dateAdd, startOf, isoWeek…). Pure and proleptic Gregorian over YYYY-MM-DD texts, no clock and no locale; fixtures/records-query.json bucketCases lock it. A date is a calendar day (spec §4.3); a timestamp’s day is the first ten characters of its ISO text.

Structs

CalendarDay

Enums

DateBucket

The time buckets a query groups dates by.

Constants

DATE_BUCKETS

Functions

date_bucket

A date’s bucket key: day 2026-10-05, week 2026-W41 (ISO), month 2026-10, quarter 2026-Q4, year 2026; None when the text holds no date that precise.

day_from_number

day_number

VAPP-191: the days since 1970-01-01 of a calendar day (negative before; Howard Hinnant’s days_from_civil), and back (dayNumber / dayFromNumber in dates.ts).

day_of_year

1-based day of the year.

days_in_month

format_day

YYYY-MM-DD.

is_leap_year

iso_week

The ISO week (Monday first, week 1 holds the first Thursday): (year, week).

iso_weeks_in_year

ISO 8601 weeks in a year: 53 when it starts on a Thursday (or a Wednesday in a leap year).

parse_day

The calendar day at the start of text (YYYY-MM-DD, then the end, T or a space); None when it is not a real day.

parse_month

The year and month at the start of text (YYYY-MM, then the end or -).

parse_year

The year at the start of text (YYYY, then the end or -).

weekday_of

0 = Sunday (Sakamoto’s method).