[Haskell-cafe] Problem with class Control.Monad.Error noMsg usage

[Ross Paterson]

On Tue, Dec 21, 2010 at 03:28:22PM +0000, Aaron Gray wrote:
> I have been trying to build the Scheme in 24 Hours on WikiBooks :-
> 
>     http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_Hours
> 
>     http://jonathan.tang.name/files/scheme_in_48/code/listing10.hs
> 
> But I am getting an error :- 
> 
>     scheme.hs:289:6: `noMsg' is not a (visible) method of class `Error'
> 
>     scheme.hs:290:6:
>          `strMsg' is not a (visible) method of class `Error'

I don't get that here.  Perhaps you're using an old version of monads-fd
(0.1.0.0).  I'd recommend installing mtl-2.0.1.0 instead.