[Haskell-cafe] throwing sugar into the void.
ekarttun at cs.helsinki.fi
Sun May 7 03:53:27 EDT 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
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