npm i @react-hook/previous

A React hook that stores a value from the previous render.

Quick Start

``jsx harmony
import * as React from 'react'
import usePrevious from '@react-hook/previous'

const useChanged = (onChange) => {
const [status, setStatus] = React.useState('off')
const prevStatus = usePrevious(status)

React.useEffect(() => {
if (status !== prevStatus) onChange()
}, [status])

return [status, setStatus]
}
`

API

$3

`ts
const usePrevious: (
value: T,
initialValue?: T | undefined
) => T | undefined
`

| Argument | Type | Default | Required? | Description |
| ------------ | --------------- | ----------- | --------- | ------------------------------------------------------------------------- |
| value | T | | Yes | The current value |
| initialValue | T | undefined | undefined` | No | The value returned by the hook when the current value has not yet changed |

LICENSE

MIT