export type RecurrenceFrequency = 'secondly' | 'minutely' | 'hourly' | 'daily' | 'weekly' | 'monthly' | 'yearly';
export interface WeekdayOrdinal {
    ordinal: number;
    weekday: number;
}
export interface RecurrenceRule {
    frequency: RecurrenceFrequency;
    interval: number;
    count?: number;
    until?: unknown;
    byWeekday?: number[];
    byWeekdayOrdinal?: WeekdayOrdinal[];
    byMonthDay?: number[];
    byMonth?: number[];
    byWeek?: number[];
    exDates?: unknown[];
    rDates?: unknown[];
}
export interface RecurrenceIterator {
    next(): {
        value: unknown;
        done: boolean;
    } | {
        value: undefined;
        done: true;
    };
    previous(): {
        value: unknown;
        done: boolean;
    } | {
        value: undefined;
        done: true;
    };
}
export declare function recurrence(start: unknown, rule: RecurrenceRule): RecurrenceIterator;
export declare function take(iter: RecurrenceIterator, n: number): unknown[];
export declare function skip(iter: RecurrenceIterator, n: number): unknown[];
export declare function between(start: unknown, rule: RecurrenceRule, rangeStart: unknown, rangeEnd: unknown): unknown[];
export declare function parseRRule(input: string): RecurrenceRule;
export declare function formatRRule(rule: RecurrenceRule): string;