Sebastian Markbåge
60016c448b
* Add options for forked entry points We currently fork .fb.js entry points. This adds a few more options. .modern.fb.js - experimental FB builds .classic.fb.js - stable FB builds .fb.js - if no other FB build, use this for FB builds .experimental.js - experimental builds .stable.js - stable builds .js - used if no other override exists This will be used to have different ES exports for different builds. * Switch React to named exports * Export named exports from the export point itself We need to re-export the Flow exported types so we can use them in our code. We don't want to use the Flow types from upstream since it doesn't have the non-public APIs that we have. This should be able to use export * but I don't know why it doesn't work. This actually enables Flow typing of React which was just "any" before. This exposed some Flow errors that needs fixing. * Create forks for the react entrypoint None of our builds expose all exports and they all differ in at least one way, so we need four forks. * Set esModule flag to false We don't want to emit the esModule compatibility flag on our CommonJS output. For now we treat our named exports as if they're CommonJS. This is a potentially breaking change for scheduler (but all those apis are unstable), react-is and use-subscription. However, it seems unlikely that anyone would rely on this since these only have named exports. * Remove unused Feature Flags * Let jest observe the stable fork for stable tests This lets it do the negative test by ensuring that the right tests fail. However, this in turn will make other tests that are not behind __EXPERIMENTAL__ fail. So I need to do that next. * Put all tests that depend on exports behind __EXPERIMENTAL__ Since there's no way to override the exports using feature flags in .intern.js anymore we can't use these APIs in stable. The tradeoff here is that we can either enable the negative tests on "stable" that means experimental are expected to fail, or we can disable tests on stable. This is unfortunate since some of these APIs now run on a "stable" config at FB instead of the experimental. * Switch ReactDOM to named exports Same strategy as React. I moved the ReactDOMFB runtime injection to classic.fb.js Since we only fork the entrypoint, the `/testing` entrypoint needs to be forked too to re-export the same things plus `act`. This is a bit unfortunate. If it becomes a pattern we can consider forking in the module resolution deeply. fix flow * Fix ReactDOM Flow Types Now that ReactDOM is Flow type checked we need to fix up its types. * Configure jest to use stable entry for ReactDOM in non-experimental * Remove additional FeatureFlags that are no longer needed These are only flagging the exports and no implementation details so we can control them fully through the export overrides.
React · 
React is a JavaScript library for building user interfaces.
- Declarative: React makes it painless to create interactive UIs. Design simple views for each state in your application, and React will efficiently update and render just the right components when your data changes. Declarative views make your code more predictable, simpler to understand, and easier to debug.
- Component-Based: Build encapsulated components that manage their own state, then compose them to make complex UIs. Since component logic is written in JavaScript instead of templates, you can easily pass rich data through your app and keep state out of the DOM.
- Learn Once, Write Anywhere: We don't make assumptions about the rest of your technology stack, so you can develop new features in React without rewriting existing code. React can also render on the server using Node and power mobile apps using React Native.
Learn how to use React in your own project.
Installation
React has been designed for gradual adoption from the start, and you can use as little or as much React as you need:
- Use Online Playgrounds to get a taste of React.
- Add React to a Website as a
<script>tag in one minute. - Create a New React App if you're looking for a powerful JavaScript toolchain.
You can use React as a <script> tag from a CDN, or as a react package on npm.
Documentation
You can find the React documentation on the website.
Check out the Getting Started page for a quick overview.
The documentation is divided into several sections:
You can improve it by sending pull requests to this repository.
Examples
We have several examples on the website. Here is the first one to get you started:
function HelloMessage({ name }) {
return <div>Hello {name}</div>;
}
ReactDOM.render(
<HelloMessage name="Taylor" />,
document.getElementById('container')
);
This example will render "Hello Taylor" into a container on the page.
You'll notice that we used an HTML-like syntax; we call it JSX. JSX is not required to use React, but it makes code more readable, and writing it feels like writing HTML. If you're using React as a <script> tag, read this section on integrating JSX; otherwise, the recommended JavaScript toolchains handle it automatically.
Contributing
The main purpose of this repository is to continue to evolve React core, making it faster and easier to use. Development of React happens in the open on GitHub, and we are grateful to the community for contributing bugfixes and improvements. Read below to learn how you can take part in improving React.
Code of Conduct
Facebook has adopted a Code of Conduct that we expect project participants to adhere to. Please read the full text so that you can understand what actions will and will not be tolerated.
Contributing Guide
Read our contributing guide to learn about our development process, how to propose bugfixes and improvements, and how to build and test your changes to React.
Good First Issues
To help you get your feet wet and get you familiar with our contribution process, we have a list of good first issues that contain bugs which have a relatively limited scope. This is a great place to get started.
License
React is MIT licensed.