Hello café,I've never written an Alternative instance for a newtype yet that doesn't look like this:
instance Alternative T where empty = T empty T x <|> T y = T (x <|> y)
Why does newtype deriving not work for Alternative? (It works fine for Monoid.)
Thanks, Martijn. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
