> For the complete documentation index, see [llms.txt](https://docs.react-async.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.react-async.com/master/getting-started/upgrading.md). # Upgrading ## Upgrade to v9 The rejection value for failed requests with `useFetch` was changed. Previously it was the Response object. Now it's an Error object with `response` property. If you are using `useFetch` and are using the `error` value, expecting it to be of type Response, you must now use `error.response` instead. ## Upgrade to v8 All standalone helper components were renamed to avoid import naming collision. * `` was renamed to ``. * `` was renamed to ``. * `` was renamed to ``. * `` was renamed to `` was renamed to ``. > A [codemod](https://github.com/async-library/react-async/tree/master/codemods) is available to automate the upgrade. The return type for `run` was changed from `Promise` to `undefined`. You should now use the `promise` prop instead. This is a manual upgrade. See [`promise`](/master/api/state.md#promise) for details. ## Upgrade to v6 * `` was renamed to ``. * Some of the other helpers were also renamed, but the old ones remain as alias. * Don't forget to deal with any custom instances of `` when upgrading. > A [codemod](https://github.com/async-library/react-async/tree/master/codemods) is available to automate the upgrade. ## Upgrade to v4 * `deferFn` now receives an `args` array as the first argument, instead of arguments to `run` being spread at the front of the arguments list. This enables better interop with TypeScript. You can use destructuring to keep using your existing variables. * The shorthand version of `useAsync` now takes the `options` object as optional second argument. This used to be `initialValue`, but was undocumented and inflexible.