dmwit · October 28, 2019 20:38
diff --git a/Zip.hs b/Zip.hs
 {-# LANGUAGE DeriveFunctor #-}
 import Control.Monad.Zip

 data Zip f a = P a | V (f a)
 	deriving (Eq, Ord, Read, Show, Functor)

 instance MonadZip f => Applicative (Zip f) where
 	pure = P
 	P f <*> P x = P (f x)
 	P f <*> V xs = V (f <$> xs)
 	V fs <*> P x = V (($x) <$> fs)
 	V fs <*> V xs = V (mzipWith ($) fs xs)
	{-# LANGUAGE DeriveFunctor #-}
	import Control.Monad.Zip

	data Zip f a = P a \| V (f a)
	deriving (Eq, Ord, Read, Show, Functor)

	instance MonadZip f => Applicative (Zip f) where
	pure = P
	P f <*> P x = P (f x)
	P f <*> V xs = V (f <$> xs)
	V fs <*> P x = V (($x) <$> fs)
	V fs <*> V xs = V (mzipWith ($) fs xs)