[Haskell-cafe] Arrow instance of function type [a] -> [b]

[David Barbour]

On Wed, Jul 6, 2011 at 6:04 AM, Markus Läll <markus.l2ll at gmail.com> wrote:

> Is it possible to define an Arrow instance of list to list functions?
>
> import Control.Arrow
> import Control.Category
>
> type X a b = [a] -> [b]
>

You need a newtype here. (->) is already an arrow.
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