/**
 * Calculates the modulus 11 check digit for a given string.
 *
 * @param {string} str - The string to calculate the check digit for.
 * @returns {number} The calculated check digit (1-11).
 *
 * @example
 * ```typescript
 * mod11("0019000009011497186016852452211467586000010265"); // 6
 * ```
 */
export declare const mod11: (str: string) => number;