intervalsOverlapUtc

Signature

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

import { intervalsOverlapUtc } from "@northguild/gmt/utc/interval";

Return true when intervals [aStart, aEnd] and [bStart, bEnd] share at least one instant.

• Uses Temporal.Instant.compare for comparison (same instant semantics).
• Adjacent intervals (e.g. aEnd === bStart) do NOT overlap — returns false.
• Returns false if either interval is invalid (start > end).
• Returns false on invalid input (wrong type, malformed strings, leap seconds).

Parameters

Parameter	Type	Description
aStart	string	ISO 8601 UTC datetime string for the first interval start
aEnd	string	ISO 8601 UTC datetime string for the first interval end
bStart	string	ISO 8601 UTC datetime string for the second interval start
bEnd	string	ISO 8601 UTC datetime string for the second interval end

Returns

true if intervals overlap, or false on invalid input

Examples

intervalsOverlapUtc("2024-01-01T00:00:00Z", "2024-06-30T23:59:59Z", "2024-04-01T00:00:00Z", "2024-12-31T23:59:59Z") // true
intervalsOverlapUtc("2024-01-01T00:00:00Z", "2024-06-30T23:59:59Z", "2024-07-01T00:00:00Z", "2024-12-31T23:59:59Z") // false (adjacent)
intervalsOverlapUtc("2024-01-01T00:00:00Z", "2024-06-30T23:59:59Z", "2024-07-02T00:00:00Z", "2024-12-31T23:59:59Z") // false (disjoint)
intervalsOverlapUtc("invalid", "2024-06-30T23:59:59Z", "2024-04-01T00:00:00Z", "2024-12-31T23:59:59Z") // false

Source

utc/interval/intervalsOverlapUtc.ts