[Yhc] Could you please explain the interface to the type checker?

Hi yhc developers, I'm contemplating the possibility of using Chameleon as a front end (well type checker) for yhc. http://www.comp.nus.edu.sg/~sulzmann/chameleon/download/haskell.html Would one of you be able to describe the interface of the type checker (which I presume is Type.typeTopDecls)? Cheers, Bernie. PS I don't want to tread on anyone's toes, so if you have a fancy new type checker in the pipeline I would like to hear about that too.