What walled garden, could you elaborate? Dart is an open-source project and compiles to JS. Not unlike CoffeeScript or TypeScript. The cool thing that makes me

What walled garden, could you elaborate? Dart is an open-source project and compiles to JS. Not unlike CoffeeScript or TypeScript. The cool thing that makes me excited about dart2js is that Dart is a much better language than JS itself (not a high bar, but still) and that dart2js as of late is producing more efficient code than hand-coded JS because they leverage Dart's more ubiquitous typing as well as other tricks.