CoffeeScript vs Google Web Toolkit

CoffeeScript is a language that compiles to JavaScript, so its output runs without a CoffeeScript interpreter. It can use existing JavaScript libraries, and JavaScript can use libraries written in CoffeeScript. Version 2 produces modern JavaScript syntax, including classes and arrow functions, and supports async functions and JSX. The `coffee` command runs scripts, compiles `.coffee` files to `.js`, and opens an interactive REPL; it can also generate inline or external source maps. Install it through npm, globally or as a project dependency. The core compiler can run in a browser or another JavaScript environment, while the command-line utility requires Node 6 or later. Its Node API compiles CoffeeScript strings and can return source maps or an abstract syntax tree. Babel transpilation is available when `@babel/core` is installed. The integrations section links to build tools, editors, frameworks, linters, formatters, and testing resources. JSX output always needs transpilation, and users must ensure their runtime supports the modern features they use or transpile the result. CoffeeScript is free and open source.

Google Web Toolkit (GWT) is a free, open-source Java framework for building AJAX web applications. Its compiler converts Java applications into JavaScript and HTML for browser use, and the SDK includes the core libraries and compiler. Deferred binding generates browser-specific code at compile time, while the compiler can create separate application versions for different browsers and languages. Applications can communicate asynchronously with servers through GWT RPC or JSON. An Eclipse plugin provides IDE support and an option to install the SDK. The developer guide covers deployment to Google App Engine, JUnit unit testing and Emma code coverage; documentation also includes SafeHtml guidance for XSS prevention and GWT RPC XSRF protection. GWT is licensed under Apache 2.0 for non-commercial, commercial and enterprise applications. Version 2.13.1 is listed for Windows, Mac OS X and Linux. Development mode and the compiler periodically send a timestamp ID and product version to Google; Google says it does not log cookies or personal information. The webAppCreator utility has been deprecated since version 2.11.0.