Re: [Haskell-cafe] throwing sugar into the void.

7 May 2006

      On 07.05 01:12, Marc A. Ziegert wrote:
...
data Type a
typeOf :: a -> Type a
typeOf = undefined
#define TYPE(a) (undefined::Type (a))
...
sizeOf :: (Storable a) => Type a -> Int
I think the name Proxy is used for this in other places.

data Proxy a = Proxy
class Storable a where
    ...
    sizeOf :: Proxy a -> Int

proxy :: a -> Proxy a
proxy _ = Proxy

Note here that there are no undefined values used thus one does not need to be
careful with evaluation.

- Einar Karttunen