If you want the "LogTree2" typeclass to have multiple type arguments (which it looks like you do, from the definition of "evaluator"), you need to define it as 

class (Show a, Num a) => LogTree2 a t where

--Will

On Sat, Aug 29, 2015 at 6:45 PM, David Banas <capn.freako@gmail.com> wrote:
Hi all,

I can’t figure out why this is invalid:

class (Show a, Num a) => LogTree2 a where
    evaluator :: (LogTree2 a) t => t -> SizedVector a -> SizedVector a

error| ‘LogTree2’ is applied to too many type arguments In the type ‘(LogTree2 a) t => t -> SizedVector a -> SizedVector a’ In the class declaration for ‘LogTree2’

Can anyone help me understand?

Thanks,
-db


_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe