[Haskell-cafe] ANNOUNCE: type-level-natural-number and friends!

[Henning Thielemann]

Gregory Crosswhite schrieb:

>  On 10/14/10 1:35 AM, Henning Thielemann wrote:

>> Is there also a 'reify' function, that allows to convert an Int or Peano
>> value locally to a type level number?
>>
>> reifyInteger :: Integer ->  (forall n. Nat n =>  n ->  a) ->  a
>>
> 
> Not presently, but it is easy to implement such a function:
> 
>     reifyInt :: Int -> (forall n. NaturalNumber n => N n -> a) -> a
>     reifyInt i f =
>         case intToUnknownN i of
>             UnknownN n -> f n
> 
> Is this what you were thinking of?

I don't find the string "Unknown" in any of the three
type-level-natural* packages.