Hi Simon. I think you deserve a reply on these questions as at their heart is an important point which I believe remains unanswered. Simon Peyton-Jones wrote:
Dear Template Haskell colleagues
I sent three messages to the TH list a month ago. Here's one of them: the others concerned the conversions TH.Syntax <-> HsSyn; I'll fwd them in the next two messages
I didn't get a single reply to any of the three. Either the TH mailing list is broken, or else you are all busy with other stuff. (After all, all three did ask for volunteers, in one form or another.)
Does anyone care?
I am not using TH personally due to lack of time (as with most of my "free time" projects for the past year or two - job, family etc, etc). Never-the-less, I think TH is important because it explores, in the context of the SML family of languages and particularly non-strict Haskell, the equivalent of one of the more powerful features available in Lisp - macros. Despite all the work you and your collaborators have done I believe that it remains to be seen in a large, mature project whether the methodology of TH is of such practical benefit to Haskell as macros have been to Lisp and even templates to C++. I'm inspired particularly by the Blitz++ C++ numerical library and the beautiful exposition of how to compile Prolog into Common Lisp made by Peter Norvig in his book "Paradigms of Artificial Intelligence Programming: Case Studies in Common Lisp", if you need any inspiration. I also think that TH could find uses in foreign function interface marshalling.
I'm busy implementing GADTs at the moment, so TH has a somewhat back seat. It'll probably stay that way unless there are some signs of life in the TH ranks.
This email provides nothing concrete for you, for which I apologize, but I hope that you and your colleagues don't drop the topic in the longer term as I feel you have only scratched the surface in terms of practical research potential. Cheers Mike Thomas.