Hi Nicolas,
It's not intentional, but Iavor is aware of this, and we want to change it.
I'm CC-ing him as he might know more about what the current plan is.
Cheers,
Pedro
On Sat, Aug 24, 2013 at 3:20 PM, Nicolas Trangez
Hello Cafe,
I was playing around with TypeLits in combination with Typeable (using GHC 7.7.7.20130812 FWIW), but was surprised to find Symbols aren't Typeable, and as such the following doesn't work. Is this intentional, or am I missing something?
Thanks,
Nicolas
{-# LANGUAGE DataKinds, KindSignatures, DeriveFunctor, DeriveDataTypeable #-} module Main where
import Data.Typeable import GHC.TypeLits
data NoSymbol n a b = NoSymbol a b deriving (Typeable)
data WithSymbol (n :: Symbol) a b = WithSymbol a b deriving (Typeable)
data Sym deriving (Typeable)
main :: IO () main = do print $ typeOf (undefined :: NoSymbol Sym Int Int)
let d = undefined :: WithSymbol "sym" Int Int {- print $ typeOf d
No instance for (Typeable Symbol "sym") arising from a use of 'typeOf' -}
return ()
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