--!strict
-- upstream: https://github.com/facebook/react/blob/56e9feead0f91075ba0a4f725c9e4e343bca1c67/packages/react/src/index.js
--[[*
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @flow
 *]]