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| /** | |
| * This method is like `find` except that it returns the key of the first | |
| * element `predicate` returns truthy for instead of the element itself. | |
| * | |
| * @since 1.1.0 | |
| * @category Object | |
| * @param {Object} object The object to inspect. | |
| * @param {Function} predicate The function invoked per iteration. | |
| * @returns {string|undefined} Returns the key of the matched element, | |
| * else `undefined`. | |
| * @see find, findIndex, findLast, findLastIndex, findLastKey | |
| * @example | |
| * | |
| * const users = { | |
| * 'barney': { 'age': 36, 'active': true }, | |
| * 'fred': { 'age': 40, 'active': false }, | |
| * 'pebbles': { 'age': 1, 'active': true } | |
| * } | |
| * | |
| * findKey(users, ({ age }) => age < 40) | |
| * // => 'barney' (iteration order is not guaranteed) | |
| */ | |
| function findKey(object, predicate) { | |
| let result | |
| if (object == null) { | |
| return result | |
| } | |
| Object.keys(object).some((key) => { | |
| const value = object[key] | |
| if (predicate(value, key, object)) { | |
| result = key | |
| return true | |
| } | |
| }) | |
| return result | |
| } | |
| export default findKey |