Covariant, contravariant, and invariant functor ex
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| Language | Haskell |
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| Owner | rightfold |
| Created | 7 years ago |
| Modified | 7 years ago |
| Visibility | Public |
module Main
( main
) where
import Data.Foldable (traverse_)
import Data.List (intercalate)
data Variance =
Co | Contra | In
deriving (Bounded, Enum)
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