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Andrew Clark
fa2f82addc
Depends on: - #28317 - #28320 --- Changes the behavior of the JSX runtime to pass through `ref` as a normal prop, rather than plucking it from the props object and storing on the element. This is a breaking change since it changes the type of the receiving component. However, most code is unaffected since it's unlikely that a component would have attempted to access a `ref` prop, since it was not possible to get a reference to one. `forwardRef` _will_ still pluck `ref` from the props object, though, since it's extremely common for users to spread the props object onto the inner component and pass `ref` as a differently named prop. This is for maximum compatibility with existing code — the real impact of this change is that `forwardRef` is no longer required. Currently, refs are resolved during child reconciliation and stored on the fiber. As a result of this change, we can move ref resolution to happen only much later, and only for components that actually use them. Then we can remove the `ref` field from the Fiber type. I have not yet done that in this step, though.
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 />);