Microsoft has open source their research project TouchDevelop, which contains about 160K lines of code mostly written in TypeScript.
TouchDevelop is a touch-friendly tool for creating mobile applications or websites in a browser using HTML5 and TypeScript. It comes with a debugger, profiler, logging, and a physics engine for games. It can be used to develop locally on touch-enabled Android, iOS, and Windows devices or on a Windows, Linux or Mac laptop with mouse and keyboard. It can target all those platforms and Arduino. It can connect to a back-end hosted by Microsoft on Azure, enabling sharing and community collaboration.
A product of Microsoft Research, TouchDevelop did not draw our attention when it was first announced in 2012. While the tool now supports three skill levels – Beginner, Coder, and Expert –, TouchDevelop feels awkward for the casual developer being more targeted at children and students having fun creating their first mobile app or website. While the tool’s interface is optimized for touch, and one could theoretically develop apps on a tablet or even a phone, it is hard to think developers will leave their power IDEs for it.
The reason we are covering this is the fact that Microsoft has made the source code of TouchDevelop available under the permissive license MIT. Developers can reuse parts of it or learn from its about 160,000 LoC, mostly TypeScript with some CSS and HTML. An important component of the project is the editor with intellisense.
According to Michał Moskal, a MS researcher, Microsoft will continue to work on TouchDevelop, inviting the community to contribute.