//#region src/predicate/is-key-in.d.ts
/**
 * Checks whether `key` exists in `object` — including inherited properties, as
 * the `in` operator does — and acts as a type guard that narrows the **key** to
 * those that actually exist in the object. This is useful for validating a
 * union of candidate keys: on a positive result, the key is narrowed to the
 * subset present in the object. The argument order mirrors the native
 * `key in object` expression. It also guards against prototype-pollution keys
 * (`__proto__`, `constructor`).
 *
 * To narrow the **object** instead of the key, use {@link isIn}.
 * @param key - The property key (often a union of candidates) to look for.
 * @param object - The object to check.
 * @returns `true` if `key` is in `object` (own or inherited); narrows `key` to
 * the keys that exist in `object`.
 * @example
 * // Narrows a union of candidate keys to those present in the object
 * const object = {foo: 1, bar: 2};
 * const key = 'foo' as 'foo' | 'bar' | 'baz';
 * if (isKeyIn(key, object)) {
 *   object[key]; // `key` is now `'foo' | 'bar'`
 * }
 */
declare const isKeyIn: <Key extends PropertyKey, ObjectType extends object>(key: Key, object: ObjectType) => key is Key & keyof ObjectType & {};
//#endregion
export { isKeyIn };