Asynchronous side effects, without the nonsense
npm install use-async-effect!Logo


---
:running: Asynchronous side effects, without the nonsense.
``javascript`
useAsyncEffect(async () => {
await doSomethingAsync();
});
``
npm install use-async-effect`
or`
yarn add use-async-effect
This package ships with TypeScript and Flow types.
The API is the same as React's useEffect(), except for some notable differences:
- The destroy function is passed as an optional second argument:
`javascript`
useAsyncEffect(callback, dependencies?);
useAsyncEffect(callback, onDestroy, dependencies?);
- The async callback will receive a single function to check whether the callback is still mounted:
`javascript
useAsyncEffect(async isMounted => {
const data1 = await fn1();
if (!isMounted()) return;
const data2 = await fn2();
if (!isMounted()) return;
doSomething(data1, data2);
});
`
> Mounted means that it's running in the current component. It becomes unmounted if the component unmounts, or if the component is re-rendered and the callback is dropped and a new one is called.
Basic mount/unmount
`javascript`
useAsyncEffect(async () => console.log('mount'), () => console.log('unmount'), []);
Omitting destroy
`javascript`
useAsyncEffect(async () => console.log('mount'), []);
Handle effect result in destroy
`javascript`
useAsyncEffect(() => fetch('url'), (result) => console.log(result));
Making sure it's still mounted before updating component state
`javascript/users/${id}
useAsyncEffect(async isMounted => {
const data = await fetch().then(res => res.json());``
if (!isMounted()) return;
setUser(data);
}, [id]);