[Haskell-cafe] Re: Can't make a derived instance of `Typeable (A B)': `A' has arguments of kind other than `*'

Christopher Done chrisdone at googlemail.com
Fri Sep 24 16:20:45 EDT 2010

Just for what it's worth, the following does work:

newtype AMaybe = AMaybe { unMaybe :: A Maybe }
deriving instance Typeable AMaybe

Which leads me to be kind of baffled by the above error message.

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