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Andrew Clark
0b3b8a6a35
Follow up to #28768. The modern JSX runtime (`jsx`) does not need to check if each prop is a direct property with `hasOwnProperty` because the compiler always passes a plain object. I'll leave the check in the old JSX runtime (`createElement`) since that one can be called manually with any kind of object, and if there were old user code that relied on this for some reason, it would be using that runtime.
react
React is a JavaScript library for creating user interfaces.
The react package contains only the functionality necessary to define React components. It is typically used together with a React renderer like react-dom for the web, or react-native for the native environments.
Note: by default, React will be in development mode. The development version includes extra warnings about common mistakes, whereas the production version includes extra performance optimizations and strips all error messages. Don't forget to use the production build when deploying your application.
Usage
import { useState } from 'react';
import { createRoot } from 'react-dom/client';
function Counter() {
const [count, setCount] = useState(0);
return (
<>
<h1>{count}</h1>
<button onClick={() => setCount(count + 1)}>
Increment
</button>
</>
);
}
const root = createRoot(document.getElementById('root'));
root.render(<Counter />);