[Haskell-cafe] Making MVar and Chan Instances of Typeable

Benjamin Franksen benjamin.franksen at bessy.de
Fri Nov 5 09:07:32 EST 2004

On Friday 05 November 2004 16:20, MR K P SCHUPKE wrote:
> nstance Typeable a => Typeable (MVar a) where
>   typeOf (x::x) =
>     mkAppTy (mkTyCon "Control.Concurrent.MVar.MVar") [typeOf
> (undefined::x)]

I may be missing something but this look like an open recursion to me. The 
type 'x' is 'MVar a', but what is needed is the 'a'.


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