/**
 * Checks if a given key is a deep key.
 *
 * A deep key is a string that contains a dot (.) or square brackets with a property accessor.
 *
 * @param {PropertyKey} key - The key to check.
 * @returns {boolean} - Returns true if the key is a deep key, otherwise false.
 *
 * Examples:
 *
 * isDeepKey('a.b') // true
 * isDeepKey('a[b]') // true
 * isDeepKey('a') // false
 * isDeepKey(123) // false
 * isDeepKey('a.b.c') // true
 * isDeepKey('a[b][c]') // true
 */
declare function isDeepKey(key: PropertyKey): boolean;

export { isDeepKey };