Ceylon progress report

Posted by    |      

Hrm, I notice it's been just over three months since I semi-accidentally announced the existence of the Ceylon project, and I guess I feel like you folks deserve some kind of progress report! At the time, I very much regretted the fact that the project became public knowledge before I was really prepared to socialize it, but in retrospect it was the best thing ever for us. That's where we got Stef and Tako and Sergej and Ben from, along with the other folks who are signing up to get involved in development. Unfortunately, we're still working in a private github repo, which is certainly not ideal, but it's helping keep us focused on getting actual code written.

So here's what we have so far:

  • a 125 page language specification (with some open issues and vague sections),
  • a parser and typesafe syntax tree for the whole language,
  • a compiler frontend (type checker/analyzer) for about 85% of the language,
  • a compiler backend that integrates the frontend with javac's bytecode generation for perhaps 40% of the language, and
  • the skeleton of a model loader that builds a metamodel of precompiled .class files (essential for incremental compilation and interoperation with Java).

The frontend of the compiler (the bit that analyzes the semantics of the code, assigns types to things, and reports programming errors) is basically done already. Certainly all the hard bits are finished, including stuff like generics, covariance, subtyping, refinement, member types, union types, definite assignment and definite return checking, type argument inference, etc. The few missing features could be finished off pretty quickly if there were any real urgency, but we may as well wait for the backend to catch up.

Development of the backend and model loader is now completely in the hands of volunteers from the community, and, frankly, it's going really well so far. We'll do an initial alpha-quality release of the compiler when we're happy that the backend is in a usable form.

I'm not going to promise any exact date for the first release, nor even the exact feature set - but I'm guessing it will happen within the next three months, and that it will include a really decent slab of the language defined by the specification. At that point, we'll hopefully be able to start putting some resources into the SDK and IDE.


Back to top