React: v0.4.0 Release

React

• Switch from using id attribute to data-reactid to track DOM nodes. This allows you to integrate with other JS and CSS libraries more easily.
• Support for more DOM elements and attributes (e.g., <canvas>)
• Improved server-side rendering APIs. React.renderComponentToString(<component>, callback) allows you to use React on the server and generate markup which can be sent down to the browser.
• prop improvements: validation and default values. Read our blog post for details...
• Support for the key prop, which allows for finer control over reconciliation. Read the docs for details...
• Removed React.autoBind. Read our blog post for details...
• Improvements to forms. We've written wrappers around <input>, <textarea>, <option>, and <select> in order to standardize many inconsistencies in browser implementations. This includes support for defaultValue, and improved implementation of the onChange event, and circuit completion. Read the docs for details...
• We've implemented an improved synthetic event system that conforms to the W3C spec.
• Updates to your component are batched now, which may result in a significantly faster re-render of components. this.setState now takes an optional callback as it's second parameter. If you were using onClick={this.setState.bind(this, state)} previously, you'll want to make sure you add a third parameter so that the event is not treated as the callback.

JSX

• Support for comment nodes <div>{/* this is a comment and won't be rendered */}</div>
• Children are now transformed directly into arguments instead of being wrapped in an array E.g. <div><Component1/><Component2/></div> is transformed into React.DOM.div(null, Component1(null), Component2(null)). Previously this would be transformed into React.DOM.div(null, [Component1(null), Component2(null)]). If you were using React without JSX previously, your code should still work.

react-tools

• Fixed a number of bugs when transforming directories
• No longer re-write require()s to be relative unless specified