/**
 * Converts a string to title case and removes special characters.
 *
 * @since 1.0.0
 *
 * @param {string} [str=''] - The string to convert to title case.
 *
 * @return {string} - The string converted to title case.
 *
 * @example
 *
 * upperCase('Hello_world');
 * // => 'HELLO WORLD'
 *
 * upperCase('life-is_beautiful');
 * // => 'LIFE IS BEAUTIFUL'
 */
declare const upperCase: (str?: string) => string;
export default upperCase;