I'm trying to write Applicative for this type data Choice a = ColumnA a | ColumnB a I wrote a Functor instance: instance Functor Choice where fmap f (Co
Still not a hundred percent shure how to make instances of the more complex types. Have this: data CouldBe a = Is a | Lost deriving (Show, Ord) Made an ins
I'm trying to make Twice a member of applicative, but I am getting "Conflicting definitions for `a'" in the functor implementation: Also I'm not sure how to imp
I'm learning Haskell and trying to do exercises from book Haskell Programming from first principles and I'm stack trying to write applicative for Pair type da
Time and again I read the term effectful, but I am still unable to give a clear definition of what it means. I assume the correct context is effectful computati