Episode Details

In this episode of Syntax, Scott and Wes talk about using React with Typescript — how to set it up, components, state, props, passing data, custom hooks, and more!

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Show Notes

04:55 - Components

• Strategies
• Example:

type Props = { value: string; } const App = (props: Props) =>

• Return type? JSX.Element
• FC or FunctionComponent
• It’s discouraged for this reason: It means that all components accept children, even if they're not supposed to
• It could be useful for a return type

12:13 - Props

• Default props:

const defaultJoke: JokeProps = { joke: 'LOL JOE', id: 'YEAH', status: 200, }; function JokeItem({ joke = defaultJoke }: JokeProps): JSX.Element { return (

{joke.joke} = {joke.id}

); }

• Because props are always destructured, you often have to make a new type for your props. You can’t just type each argument by itself.

18:38 - State

• Just like Generics, State can be inferred
• If your type is simple and you’re using useState, it just works: const [user, setUser] = useState(null);

22:27 - useEffect

• Nothing special required
• Good use of void: If you want to use a Promise function but not worry about await or .then(), you can pop a void in front of it:

useEffect(() => { console.log('Mounted'); // getJoke().then(console.log).catch(console.error); void getJoke(); }, [getJoke]);

26:09 - Refs

• Very similar to state however some interesting things with null: const ref1 = useRef(null!);
• “Instantiating the ref with a current value of null but lying t