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Josh Story
1c02b9d2bd
Adds a flag to disable legacy mode. Currently this flag is used to cause legacy mode apis like render and hydrate to throw. This change also removes render, hydrate, unmountComponentAtNode, and unstable_renderSubtreeIntoContainer from the experiemntal entrypoint. Right now for Meta builds this flag is off (legacy mode is still supported). In OSS builds this flag matches __NEXT_MAJOR__ which means it currently is on in experiemental. This means that after merging legacy mode is effectively removed from experimental builds. While this is a breaking change, experimental builds are not stable and users can pin to older versions or update their use of react-dom to no longer use legacy mode APIs.
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 />);