intervalsOverlap

Signature

intervalsOverlap(a: Interval, b: Interval): boolean

Return true when two half-open intervals share at least one instant.

• a.start < b.end && b.start < a.end. Touching intervals (a.end is b.start) do not overlap: under [start, end) the shared endpoint belongs only to the later interval.
• True exactly when intersectIntervals(a, b) is not null.
• An empty interval (start === end) overlaps an interval it lies strictly inside, and nothing else — not at an edge, not another empty interval at the same instant (GMT rule: an empty interval covers no time, so only a strictly interior position is shared).
• Compares instants: endpoints may name different zones.
• The positional intervalsOverlapUtc, intervalsOverlapZoned, intervalsOverlapDate (…) follow the same half-open rule, so touching intervals do not overlap there either.
• For zone-aligned windows (a local day, a trading session), build the endpoints with floorToZone first.
• Returns false on invalid input — either interval not an Interval, or inverted.

Parameters

Parameter	Type	Description
a	Interval	{ start, end } record of ISO 8601 instant strings
b	Interval	{ start, end } record of ISO 8601 instant strings

Returns

true if the intervals share an instant, or false on invalid input

Related types

• Interval

Examples

import { intervalsOverlap } from "@northguild/gmt/interval/compare";

intervalsOverlap({ start: "2024-01-01T09:00:00Z", end: "2024-01-01T17:00:00Z" }, { start: "2024-01-01T12:00:00Z", end: "2024-01-01T18:00:00Z" }) // true

ab

output

 

Source

interval/compare/intervalsOverlap.ts