Add instance Data a => Data (ZipList a) to base

Oleg Grenrus oleg.grenrus at
Mon Nov 4 10:55:05 UTC 2019


ZipList should be no-brainer. Someone should write a patch.

GHC seems to generate instances like below just fine for wrapper things too,
though how often `m a` is actually Data? Well probably often enough.

newtype WrappedMonad m a = WrapMonad { unwrapMonad :: m a }
   deriving (Data)

-- instance [safe] (Typeable m, Typeable a, Data (m a)) =>
--                 Data (WrappedMonad m a)

- Oleg

On 3.11.2019 16.28, Mario wrote:
> I'm surprised this is missing. All newtypes exported from 
> Control.Applicative share the same issue, with the exception of Const.
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