import { TruncateOptions } from '../types';
/**
 * Truncates a string to a specified length and adds a replacement string.
 * @param str - The string to truncate
 * @param maxLength - The maximum length of the string
 * @param options - Configuration options for truncation
 * @returns The truncated string
 * @throws {Error} If str is null or undefined
 */
export declare function truncateString(str: string, maxLength: number, options?: TruncateOptions): string;