/**
 * Split a date interval at arbitrary `points`, producing consecutive sub-intervals.
 *
 * - `points` need not be sorted — they are sorted internally before splitting.
 * - Points outside `[start, end]` are dropped; they cannot introduce a boundary that isn't
 *   inside the interval.
 * - Points exactly on `start` or `end` are dropped too — they would only produce a
 *   zero-length sub-interval at the edge, which `divideEqually`'s zero-length case is the
 *   deliberate way to express, not `splitAt`'s.
 * - Duplicate points collapse to a single boundary.
 * - Returns `[{ start, end }]` (the whole interval, unsplit) when no valid in-range point remains.
 * - Returns `[]` when `points` is not an array, when any element is not a valid ISO PlainDate
 *   string, or on invalid input (unparseable start/end, `start > end`).
 * - Accepts GMT calendar-annotated PlainDate strings — E5 (issue #78). `start`, `end`, and
 *   every element of `points` must carry the *same* calendar tag (or all be bare ISO); any
 *   mismatch returns `[]` (E5 decision of record D4) — this also makes `.equals()`'s dedup of
 *   duplicate points safe, since same-calendar `PlainDate`s compare equal correctly.
 *
 * @param start ISO PlainDate string for the interval start, optionally calendar-annotated
 * @param end ISO PlainDate string for the interval end, optionally calendar-annotated
 * @param points array of ISO PlainDate strings to split at, optionally calendar-annotated (must match `start`/`end`'s calendar)
 * @returns array of `{ start, end }` records, or `[]` on invalid input / mismatched calendars
 *
 * @example intervalSplitAtDate("2024-01-01", "2024-01-10", ["2024-01-05"]) // [{ start: "2024-01-01", end: "2024-01-05" }, { start: "2024-01-05", end: "2024-01-10" }]
 * @example intervalSplitAtDate("2024-01-01", "2024-01-10", ["2024-01-07", "2024-01-03"]) // [{ start: "2024-01-01", end: "2024-01-03" }, { start: "2024-01-03", end: "2024-01-07" }, { start: "2024-01-07", end: "2024-01-10" }]
 * @example intervalSplitAtDate("2024-01-01", "2024-01-10", ["2024-01-01", "2024-01-10", "2024-06-01"]) // [{ start: "2024-01-01", end: "2024-01-10" }] (start, end, and out-of-range points all drop)
 * @example intervalSplitAtDate("2024-01-01", "2024-01-10", []) // [{ start: "2024-01-01", end: "2024-01-10" }]
 * @example intervalSplitAtDate("invalid", "2024-01-10", ["2024-01-05"]) // []
 * @example intervalSplitAtDate("2024-01-01", "2024-01-10", ["not-a-date"]) // []
 */
export declare function intervalSplitAtDate(start: string, end: string, points: string[]): Array<{
    start: string;
    end: string;
}>;