Monoid.hs

{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE KindSignatures #-}
{-# LANGUAGE PolyKinds #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  Type.Family.Monoid
-- Copyright   :  Copyright (C) 2015 Kyle Carter
-- License     :  BSD3
--
-- Maintainer  :  Kyle Carter <kylcarte@indiana.edu>
-- Stability   :  experimental
-- Portability :  RankNTypes
--
-- Type-level @Monoid@, defined as an open type family.
--
-----------------------------------------------------------------------------

module Type.Family.Monoid where

type family Mempty :: k
type family (a :: k) <> (b :: k) :: k