Larger Scale JavaScript

When building applications on a larger scale, developers depend upon high quality authoring and tooling experiences. For applications of this scale, higher-level abstractions such as classes and other common programming patterns can be the basis for better tooling.
The Office Web Applications, which consist of hundreds of thousands of lines of JavaScript, are written primarily in a variant of Script# that is then compiled into JavaScript that can be executed on today’s browsers. Other toolsets like the Google Web Toolkit take similar approaches. More recently, transforming compiler libraries like Traceur and CoffeeScript show how syntax additions to JavaScript and even completely alternative syntaxes can be supported in today’s browsers, without changes to the runtime.
Some examples, like Dart, portend that JavaScript has fundamental flaws and to support these scenarios requires a “clean break” from JavaScript in both syntax and runtime. We disagree with this point of view. We believe that with committee participant focus, the standards runtime can be expanded and the syntactic features necessary to support JavaScript at scale can be built upon the existing JavaScript standard.