Hello Neil, Thursday, June 5, 2008, 8:54:51 PM, you wrote:

...

PS Why isn't Functor derivable?

Derive can do it: http://www.cs.york.ac.uk/~ndm/derive

I believe that Twan (the author of Functor deriving in Derive) is trying to get this suggested for Haskell' as a proper deriving.

dear GHC developers, may be it's a good idea to add such facility to ghc? [as one more H98 extension] -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com