I'm not sure what you want to do. Presumably not "replace all Ints by Floats" because that wouldn't make sense if you applied it to the type data T = MkT Int T | Nil So, can you say precisely what you want your generic function to do? What type would you like it to have? Simon | -----Original Message----- | From: glasgow-haskell-users-bounces@haskell.org [mailto:glasgow-haskell-users- | bounces@haskell.org] On Behalf Of MR K P SCHUPKE | Sent: 04 February 2004 18:43 | To: glasgow-haskell-users@haskell.org | Subject: Re: Generics... | | | I now have a vague clue how to do what I wanted. I wanted to substitute | types in place... a silly example would be to convert Ints to Floats and | Floats to Ints... | | (3 :: Int, 4.0 :: Float) -> (3.0 :: Float, 4 :: Int) | | I already have a function that will convert the input to: | | [("3",IntType),("4.0",FloatType)] | | So I can then manipulate the list in this form to: | | [("3.0",FloatType),("4",IntType)] | | All I now need to do is reconstruct back into the data structure... | | I have however been unable to find any docs on "gunfold" which I | think is the way to do this... | | If somebody point me to some documentation for gunfold, or | help in any way I would be very grateful... | | Regards, | Keean Schupke. | _______________________________________________ | Glasgow-haskell-users mailing list | Glasgow-haskell-users@haskell.org | http://www.haskell.org/mailman/listinfo/glasgow-haskell-users