On Friday 09 November 2012 17:53:54 Ertugrul Söylemez wrote:
I'm not sure if you're supposed to use the reflection library that way. The idea is simply this:
reify :: a -> (forall s. Reifies s a => Proxy s -> r) -> r
You pass in a value, any value you like actually ('reify' is fully polymorphic in 'a'), and the continuation receives a proxy that contains a type that represents that value. You can then use the 'Reifies' class to recover the original value from the type 's'. This goes with almost no runtime cost.
In particular you should not write Reifies instances yourself. Let's say you want to write a data type for modular arithmetic that encodes the modulus in its type: […]
OK, thanks for the example. So, in this approach, we drop the type parameter 'd' of kind 'Nat', and instead work with an type variable of kind *. Thanks and regards, Arie