intervalEngulfsDateTime

Signature

intervalEngulfsDateTime(aStart: string, aEnd: string, bStart: string, bEnd: string): boolean

Return true when the half-open interval B [bStart, bEnd) lies within the half-open interval A [aStart, aEnd) — every moment of B is also in A.

• Half-open: an interval holds every t with start <= t < end. B may start at A’s start and end at A’s end, because neither end is part of either interval.
• B must also overlap A, so an empty B (bStart === bEnd) counts only strictly inside A, never at an edge (CORE-6’s clampInterval clamps it away there).
• Equivalent to 4-argument intervalContainsDateTime(aStart, aEnd, bStart, bEnd).
• Uses Temporal.PlainDateTime.compare for comparison.
• Returns false if either interval is invalid (start > end).
• Returns false on invalid input (wrong type, malformed strings).

Parameters

Parameter	Type	Description
aStart	string	ISO 8601 datetime string for the outer interval start
aEnd	string	ISO 8601 datetime string for the outer interval end (excluded)
bStart	string	ISO 8601 datetime string for the inner interval start
bEnd	string	ISO 8601 datetime string for the inner interval end (excluded)

Returns

true if B lies within A, or false on invalid input

Examples

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

intervalEngulfsDateTime("2024-01-01T09:00:00", "2024-01-01T17:00:00", "2024-01-01T12:00:00", "2024-01-01T13:00:00") // true

aStartaEndbStartbEnd

output

 

Source

plain/interval/intervalEngulfsDateTime.ts