define(['../internal/baseCallback', '../internal/baseFind', '../internal/baseForOwn'], function(baseCallback, baseFind, baseForOwn) {

/**

* This method is like `_.findIndex` except that it returns the key of the

* first element `predicate` returns truthy for, instead of the element itself.

*

* If a property name is provided for `predicate` the created "_.property"

* style callback returns the property value of the given element.

*

* If an object is provided for `predicate` the created "_.matches" style

* callback returns `true` for elements that have the properties of the given

* object, else `false`.

*

* @static

* @memberOf _

* @category Object

* @param {Object} object The object to search.

* @param {Function|Object|string} [predicate=_.identity] The function invoked

* per iteration. If a property name or object is provided it is used to

* create a "_.property" or "_.matches" style callback respectively.

* @param {*} [thisArg] The `this` binding of `predicate`.

* @returns {string|undefined} Returns the key of the matched element, else `undefined`.

* @example

*

* var users = {

* 'barney': { 'age': 36, 'active': true },

* 'fred': { 'age': 40, 'active': false },

* 'pebbles': { 'age': 1, 'active': true }

* };

*

* _.findKey(users, function(chr) { return chr.age < 40; });

* // => 'barney' (iteration order is not guaranteed)

*

* // using the "_.matches" callback shorthand

* _.findKey(users, { 'age': 1 });

* // => 'pebbles'

*

* // using the "_.property" callback shorthand

* _.findKey(users, 'active');

* // => 'barney'

*/

function findKey(object, predicate, thisArg) {

predicate = baseCallback(predicate, thisArg, 3);

return baseFind(object, predicate, baseForOwn, true);

}

return findKey;

});