intervalXorAllDate

Signature

intervalXorAllDate(intervals: { start: string; end: string; }[]): { start: string; end: string; }[]

Return the symmetric difference across a list of date intervals — the set of dates covered by an odd number of the input intervals.

• List-form generalization of intervalXorDate, which is pairwise only.
• Half-open: an interval holds every t with start <= t < end. The result is every maximal run covered an odd number of times, computed as a coverage-parity sweep over the start and end boundaries. Runs end exactly at a boundary; no boundary is ever stepped by one unit, so an interval may end on the type’s last value without overflow or midnight wrap.
• Touching odd runs join into one run; an empty interval (start === end) contributes nothing. For two intervals this is exactly intervalXorDate’s pairwise result.
• Order of the input list does not matter; the result is sorted by start.
• Returns [] for an empty list, and [] when every date is covered an even number of times (e.g. two identical intervals cancel out).
• Returns [] when intervals is not an array, when any element is not a { start, end } record of valid ISO PlainDate strings, or when any element has start > end.
• Accepts RFC 9557 calendar-annotated PlainDate strings — E5 (issue #78). Since the result is date values, every start/end across the whole list must carry the same calendar tag (or all be bare ISO); any mismatch returns [] (E5 decision of record D4). Coincident sweep events are grouped with Temporal.PlainDate.compare, which orders by ISO date and ignores the calendar.

Parameters

Parameter	Type	Description
intervals	{ start: string; end: string; }[]	array of { start, end } records, optionally calendar-annotated

Returns

array of { start, end } records covered an odd number of times, or [] on invalid input / mismatched calendars

Members of each item

Member	Type	Description
start	string	The date the interval begins on, as an ISO 8601 date (YYYY-MM-DD). It keeps a calendar annotation such as [u-ca=hebrew] when the inputs carry one.
end	string	The first date after the interval, in the same format as start. It is exclusive: the interval holds everything from start up to but not including this value. It is always later than start.

Examples

import { intervalXorAllDate } from "@northguild/gmt/plain/interval";

intervalXorAllDate([{ start: "2024-01-01", end: "2024-01-10" }, { start: "2024-01-05", end: "2024-01-15" }]) // [{ start: "2024-01-01", end: "2024-01-05" }, { start: "2024-01-10", end: "2024-01-15" }]

intervals

×

×

+ add

output

 

Source

plain/interval/intervalXorAllDate.ts