/**
 * Checks if a string is in kebab-case format
 * @param str - The string to check
 * @returns boolean indicating if the string is in kebab-case
 *
 * @example
 * ```typescript
 * isKebabCase('hello-world') // => true
 * isKebabCase('helloWorld') // => false
 * ```
 * @internal This function is for internal use by the library
 */
export declare function isKebabCase(str: string): boolean;