David, I’m unclear what you are trying to achieve with #9701. I urge you to write a clear specification that we all agree about before burning cycles hacking code. There are a lot of comments at the top of Specialise.lhs. But it is, I’m afraid, a tricky pass. I could skype. Simon From: ghc-devs [mailto:ghc-devs-bounces@haskell.org] On Behalf Of David Feuer Sent: 20 October 2014 02:39 To: ghc-devs Subject: Help understanding Specialise.lhs I'm trying to figure out how to address #9701, but I'm having an awfully hard time figuring out what's going on in Specialise.lhs. I think I get the vague general idea of what it's supposed to do, based on the notes, but the actual code is a mystery to me. Is there anyone who might be able to help me get enough of a sense of it to let me do what I need? Many thanks in advance. David Feuer