Identity.hs

{-# OPTIONS -fglasgow-exts #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  Control.Comonad.Identity
-- Copyright   :  (C) 2008 Edward Kmett
-- License     :  BSD-style (see the file LICENSE)
--
-- Maintainer  :  Edward Kmett <ekmett@gmail.com>
-- Stability   :  experimental
-- Portability :  portable
--
----------------------------------------------------------------------------
module Control.Comonad.Identity where

import Control.Monad.Identity
import Control.Comonad

instance Comonad Identity where
        extract = runIdentity
        extend f x = Identity (f x)
        duplicate = Identity