/**
 * Validates if a CNPJ (Cadastro Nacional da Pessoa Jurídica) is valid.
 * Supports both numeric (version 1) and alphanumeric (version 2) CNPJ formats.
 *
 * @param {string} cnpj - The CNPJ value to be validated.
 * @param {{version?: 1|2}} [options] - Optional options:
 *    version = 1 -> validate numeric-only format (default)
 *    version = 2 -> validate both numeric and alphanumeric formats
 * @returns {boolean} True if the CNPJ is valid, false otherwise.
 *
 * @example
 * ```typescript
 * // Version 1 (numeric - default)
 * isValidCnpj("12.345.678/0001-95"); // true
 * isValidCnpj("12345678000195"); // true
 * isValidCnpj("00000000000000"); // false (reserved number)
 * isValidCnpj("12345678000190"); // false (invalid checksum)
 *
 * // Version 2 (alphanumeric)
 * isValidCnpj("Q0.SLF.MBD/7VX4-39", { version: 2 }); // true (alphanumeric)
 * isValidCnpj("Q0SLFMBD7VX439", { version: 2 }); // true (alphanumeric)
 * ```
 */
export declare const isValidCnpj: (cnpj: string, options?: {
    version?: 1 | 2;
}) => boolean;