declare const DURATIONS: {
    readonly '1m': 60;
    readonly '5m': number;
    readonly '10m': number;
    readonly '15m': number;
    readonly '30m': number;
    readonly '1h': number;
    readonly '2h': number;
    readonly '4h': number;
    readonly '6h': number;
    readonly '12h': number;
    readonly '1d': number;
    readonly '2d': number;
    readonly '7d': number;
    readonly '30d': number;
};
export declare const CACHE_PERMANENT = -1;
export declare const CACHE_NEVER = 0;
type NamedDurations = keyof typeof DURATIONS;
type NamedInterval = 'next-hour' | 'midnight' | 'end-of-week' | 'next-quarter-hour';
type NamedMaxAge = NamedDurations | NamedInterval;
/**
 * Possible values when defining max age or other time-based values.
 *
 * - 1m - Cache for 1 minute.
 * - 5m - Cache for 5 minutes.
 * - 10m - Cache for 10 minutes.
 * - 15m - Cache for 15 minutes.
 * - 30m - Cache for 30 minutes.
 * - 1h - Cache for 1 hour.
 * - 2h - Cache for 2 hours.
 * - 4h - Cache for 4 hours.
 * - 6h - Cache for 6 hours.
 * - 12h - Cache for 12 hours.
 * - 1d - Cache for 1 day.
 * - 2d - Cache for 2 days.
 * - 7d - Cache for 7 days.
 * - permanent - Cache forever.
 * - never - Do not cache at all.
 * - next-quarter-hour - Cache until the next x.15 hour (08:00, 08:15, 08:30, etc.).
 * - next-hour - Cache until the next full hour.
 * - midnight - Cache until midnight.
 * - end-of-week - Cache until end of current week (Sunday at 23:59:59).
 */
export type MaxAge = NamedMaxAge | 'permanent' | 'never' | number;
export declare function parseMaxAge(v: MaxAge, now: number): number;
export declare function isExpired(expires: number, now: number): boolean;
export declare function toTimestamp(date: Date): number;
export declare function expiresToMaxAge(expires: number, now: number): number;
export {};