Jadpo is experimental and not ready for production. These docs follow the compiler's main branch as of 5 Nov 2026. What's built · Install 0.3.0
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ReferenceTime and calendar

LanguageValues and typesStandard typesTime and calendar

DateRange

On this page

The days from one date to another, both included: 2026-10-01/2026-10-31.

Use it for bookings, holidays and reporting periods. For moments, use InstantRange, which leaves out its end. For a range of any other ordered type, use Range.

Shape

Field Type Required?
start CalendarDate Yes
end CalendarDate Yes

Its parts keep these rules, and a value that breaks one fails with the rule's name:

  • start_not_after_end: start <= end

Example

example
DateRange { start: "2026-10-01" end: "2026-10-31" }

text.parse(raw, as: DateRange) reads one from text that comes from outside. Text that isn't one at all fails malformed, such as 2026-10-31/2026-10-01, 2026-10-01 or 2026-10-01/...

This operation gives one: range.intersection.

Good to know

  • Unlike every other range, the last day counts: a one-day range has start and end on the same date.
  • range.contains, range.overlaps and range.intersection work on it.
  • == tells you whether two are the same. < and list.sort_by don't take it, so sort by one of its parts instead.

In JSON

An object of its parts, in a request, a response or json.write:

json
{"start":"2026-10-01","end":"2026-10-31"}{"start":"2026-10-25","end":"2026-10-25"}

Details

Text form, storage, how it is shown, and operations

DateRange is in the group Time and calendar, and has been in Jadpo since 0.1.0.

Text form

text.from writes one standard text form, the same form text.parse reads back: 2026-10-01/2026-10-31 and 2026-10-25/2026-10-25.

How it is stored

It is stored in one column named for the field, of type daterange. 2026-10-25/2026-10-25 is stored as daterange('2026-10-25'::date, '2026-10-25'::date, '[]').

How it is shown to people

text.format(value, locale:) shows it to people in their locale. A call also gives format:.

With locale: Locale.en_gb and format: TimeFormat.date_medium:

Value Shown
2026-10-01/2026-10-31 1 Oct 2026 – 31 Oct 2026
2026-10-25/2026-10-25 25 Oct 2026 – 25 Oct 2026

Operations

  • range.contains(range: Range<T>, value: T) -> Bool: Whether value is inside range.
  • range.intersection(a: Range<T>, b: Range<T>) -> Range<T>?: The part a and b share; none when they don't overlap.
  • range.overlaps(a: Range<T>, b: Range<T>) -> Bool: Whether a and b share at least one value.

It also takes text.parse, text.from, text.format, json.read, json.write and ==. How every standard type behaves says how they work.

Related

Markdown for agents: /docs/types/type-date-range.md.Built from Jadpo main at aee2e8f.