useSetState

Reacts setState() method, reimagined as a hook

---

Quick Start

``bash
npm install --save use-setstate
`

`jsx
import { useSetState } from "use-setstate";

const [name, setName] = useSetState("bob", newName => {
console.log(Hello ${newName}!);
});
`

Features

* Interface inspired by useState
* State change callback
* State setter can accept updater functions
* Typescript support
* Zero dependencies

Usage

The API is similar to Reacts useState() hook:

`jsx
/*
let [value, setValue] = useState(initialValue?);
*/
let [value, setValue] = useSetState(initialValue?, callback?);
`

$3

The main difference between useState() and useSetState() is the optional callback argument. When a callback is provided, useSetState() will invoke that callback after state updates have been applied via the state setter, this mimicking the behavior of Reacts setState() callback argument:

`jsx
let [isOpen, setIsOpen] = useSetState(false, () => {
console.log("open state may have changed..");
});
`

When a state change callback is invoked, useSetState() will pass the new state for that hook as the callbacks first argument:

`jsx
let [, setMoney] = useSetState(0, money => {
if (money < 0) {
console.log("Uh oh..");
}
});
`

$3

The setter function returned by useSetState() supports two methods of updating state. The first method is by direct value updates:

`jsx
let [mood, setMood] = useSetState("");

setMood("happy");

setMood("sad");
`

State can also be updated by passing an updater function to the state setter, this mimicking the behavior of updaters used with Reacts setState() method:

`jsx
let [calculation, setCalculatedValue] = useSetState();

// Updater function can update state from a function call
setCalculatedValue(Math.random);

// Updater function can update state from function call that operates on current state
setCalculatedValue(Math.sqrt);

setCalculatedValue(Math.cos);

setCalculatedValue(Math.round);
`

Run tests

`bash
npm run test
``

License

Licensed under MIT