Google recently announced open-sourcing of its JavaScript library- Closure, a JavaScript compression tools-the Closure Compiler, a code inspector- the Closure Inspector and a set of Closure Templates.

Closure will be a powerful tool-set for web developers at large. Being a cross-browser compatible library, Closure features some of the widely used helper functions and UI widgets which can be recognized from popular Google web-apps. The library, also does away with many limitations of JavaScript. It introduces object-oriented inheritance, namespaces and support for module loading with dependency resolution. For general users, this means better performing JavaScript based apps.

The Closure Compiler is an advanced compression, optimization and debugging tool for the Closure JavaScript library. The Closure Compiler is built using Java and can be used through the command line interface or a web interface from Google. A Closure inspector is also available which maps the compressed code with the original uncompressed code.

Closure, which initially started as a 20% project(Google employees use their 20% free time to innovate on their own) has come a long way and grown to be an integral part of major Google apps. The Google Code blog announcing the release, said:”

We want to hear what you think, but more importantly, we want to see what you make.

The source is available from Google Code and is distributed under the Apache License.

For download of the Closure Library, visit this page.