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intervalDifferenceTime

intervalDifferenceTime(aStart: string, aEnd: string, bStart: string, bEnd: string): { start: string; end: string; }[]

Return the portion(s) of interval A not covered by interval B.

  • Uses Temporal.PlainTime.compare for comparison.
  • Half-open: an interval holds every t with start <= t < end. A returned piece ends exactly where B starts, or starts exactly where B ends, because B’s end is not in B (CORE-6’s subtractIntervals). No piece is stepped by one unit.
  • B touching A (bStart === aEnd or bEnd === aStart), or empty, removes nothing.
  • An empty A (aStart === aEnd) has nothing left: returns []. Every returned piece is non-empty.
  • Returns [] when B fully covers A, which includes B equal to A.
  • Returns [{ start, end }] when B overlaps exactly one edge of A, leaving one piece.
  • Returns [{ start, end }, { start, end }] when B is fully inside A with gaps on both sides.
  • Returns A unchanged when B lies entirely before or after it.
  • Returns [] if either interval is invalid (start > end).
  • Returns [] on invalid input (wrong type, malformed strings).
ParameterTypeDescription
aStartstringISO 8601 time string for the first interval start
aEndstringISO 8601 time string for the first interval end
bStartstringISO 8601 time string for the second interval start
bEndstringISO 8601 time string for the second interval end

array of { start, end } records representing A minus B, or [] on invalid input

Members of each item

MemberTypeDescription
startstringThe clock time the interval begins at, as an ISO 8601 time string with no date, offset or time zone.
endstringThe first clock time 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.
import { intervalDifferenceTime } from "@northguild/gmt/plain/interval";
intervalDifferenceTime("09:00:00", "17:00:00", "12:00:00", "13:00:00") // [{ start: "09:00:00", end: "12:00:00" }, { start: "13:00:00", end: "17:00:00" }]
output 

plain/interval/intervalDifferenceTime.ts