I've read the recent posting titled "Non-derivable Typeable"
(http://www.mail-archive.com/haskell-cafe@haskell.org/msg103616.html) which
explains that Typeable cannot be automatically derived for cases where the
kind is constrained.
I'm very impressed that a solution is imminent. In the interim, can
somebody kindly suggest a workaround? I'm okay with a manual instance, but
I'd appreciate some help as to how to write one. I'm looking for a Typeable
instance for TaggedVar for the following example below (extracted from my
code).
Thank you in advance!
+Uri
{-# LANGUAGE DeriveDataTypeable, DataKinds, KindSignatures #-}
module Example where
import Data.Typeable
data Tag = TagV | TagE | TagA | TagL
deriving Typeable
newtype TaggedVar (t :: Tag) = TaggedVar Int
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