export declare type ULID = string;
export declare type ULIDFactoryArgs = {
    monotonic?: boolean;
};
export declare type ULIDFactory = (timestamp?: number) => ULID;
declare function webCryptoPRNG(): number;
declare function encodeRandom(len: number): string;
declare function validateTimestamp(timestamp: number): void;
export declare function encodeTime(timestamp: number): string;
declare function incrementBase32(str: string): string;
declare function randomChar(): string;
declare function replaceCharAt(str: string, index: number, char: string): string;
/**
 * Decode the time component of a ULID to a number representing the UNIX epoch timestamp in milliseconds.
 * @param {string}  id - A ULID string.
 * @returns {number} The UNIX epoch timestamp in milliseconds.
 */
export declare function decodeTime(id: string): number;
/**
 * @param {ULIDFactoryArgs}  args - An Object representing valid arguments for the ULID factory.
 * @returns {ULIDFactory} A function that generates ULIDs.
 */
export declare const ulidFactory: (args?: ULIDFactoryArgs) => ULIDFactory;
export declare const exportedForTesting: {
    encodeRandom: typeof encodeRandom;
    incrementBase32: typeof incrementBase32;
    randomChar: typeof randomChar;
    replaceCharAt: typeof replaceCharAt;
    validateTimestamp: typeof validateTimestamp;
    webCryptoPRNG: typeof webCryptoPRNG;
};
export {};