TypeScript - Confusion with type assertion and conditional rendering in a React component
I'm wondering if anyone has experience with I've been struggling with this for a few days now and could really use some help. I'm working on a React application using TypeScript version 4.5, and I'm working with an scenario with type assertion when conditionally rendering components based on a prop type. I have a component that receives a prop called `data`, which can either be an array of objects or `null`. I want to render a list of items if `data` is an array or show a 'No Data Available' message if it is `null`. Here's the relevant part of my code: ```tsx interface DataItem { id: number; name: string; } interface MyComponentProps { data: DataItem[] | null; } const MyComponent: React.FC<MyComponentProps> = ({ data }) => { return ( <div> {data ? ( <ul>{data.map(item => <li key={item.id}>{item.name}</li>)}</ul> ) : ( <p>No Data Available</p> )} </div> ); }; ``` When `data` is `null`, the component works as expected, but I'm getting a TypeScript behavior when `data` is potentially undefined. The behavior message states: "Object is possibly 'undefined'". I tried adding a check to see if `data` is an array using `Array.isArray(data)`, but then I face a new behavior about types not being assignable. I've also attempted to use type assertions like `data as DataItem[]` but feel like that might be risky since it doesn't properly handle cases where `data` is indeed `null`. Is there a better way to handle this conditional rendering with TypeScript that maintains type safety? Any guidance on how to resolve these type issues while keeping my code clean would be greatly appreciated! This is part of a larger application I'm building. I'm working on a desktop app that needs to handle this. My team is using Typescript for this application. What's the best practice here?