On Monday 30 October 2006 22:18, Einar Karttunen wrote:
On 29.10 19:56, John Meacham wrote:
Since DrIFT can only understand haskell source code, it can't derive instances for anything you don't have the original source to.
Ahhh, ok.
such as things in the pre-compiled libraries that come with ghc. you will likely have to write out those instances by hand.
Hmmm, seems strange that it can successfully derive for the Data.Maybe type but not the Data.Word32 type. I didn't think it would have access to any original source from my ghc install, there only seems to be hi files.
Another possibility is that you could replicate just the data declarations by hand, and use DrIFT -r to just spit out the derivations and put those in a file on their own.
How about using Template Haskell for getting the definition and then giving that to DrIFT?
Thanks for the suggestions. Daniel