[Haskell-cafe] Trouble defining `instance Arrow SF'

David Barbour dmbarbour at gmail.com
Thu Oct 27 17:29:02 CEST 2011


On Thu, Oct 27, 2011 at 5:55 AM, Captain Freako <capn.freako at gmail.com>wrote:

> SF.hs:11:10: `>>>' is not a (visible) method of class `Arrow'
> Failed, modules loaded: none.
>

import Prelude hiding ((.),id)
import Control.Category

you'll also need to define `instance Category SF`, since that is a
requirement for Arrows.
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