TypeSynonyms.hs

{-# LANGUAGE CPP                        #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE TemplateHaskell            #-}
{-# LANGUAGE TypeFamilies               #-}

#if __GLASGOW_HASKELL__ >= 702
{-# LANGUAGE DeriveGeneric              #-}
#endif

{-# OPTIONS_GHC -fno-warn-orphans #-}

{-|
Module:      Derived.TypeSynonyms
Copyright:   (C) 2014-2016 Ryan Scott
License:     BSD-style (see the file LICENSE)
Maintainer:  Ryan Scott
Stability:   Provisional
Portability: GHC

Defines data types that use type synonyms.
-}
module Derived.TypeSynonyms (TyCon(..), TyFamily(..)) where

#include "generic.h"

#if !defined(__LANGUAGE_DERIVE_GENERIC1__)
import qualified Generics.Deriving.TH as Generics
#endif

#if __GLASGOW_HASKELL__ >= 702
import           GHC.Generics (Generic)
# if __GLASGOW_HASKELL__ >= 706
import           GHC.Generics (Generic1)
# endif
#endif

import           Prelude

import           Test.QuickCheck (Arbitrary)

import           Text.Show.Deriving (deriveShow1)
import           TextShow.TH (deriveTextShow, deriveTextShow1, deriveTextShow2)

#if defined(NEW_FUNCTOR_CLASSES)
import           Text.Show.Deriving (deriveShow2)
# if !(MIN_VERSION_template_haskell(2,7,0))
import           Data.Functor.Classes (Show1(..), Show2(..), showsUnaryWith)
# endif
#endif

-------------------------------------------------------------------------------

type FakeOut a = Int
type Id a = a
type Flip f a b = f b a

-- Needed for the Generic1 instances
instance Functor ((,,,) a b c) where
    fmap f (a, b, c, d) = (a, b, c, f d)

-------------------------------------------------------------------------------

newtype TyCon a b = TyCon
    ( Id (FakeOut (Id a))
    , Id (FakeOut (Id b))
    , Id (Flip Either (Id a) (Id Int))
    , Id (Flip Either (Id b) (Id a))
    )
  deriving ( Arbitrary
           , Show
#if __GLASGOW_HASKELL__ >= 702
           , Generic
# if __GLASGOW_HASKELL__ >= 706
           , Generic1
# endif
#endif
           )

-------------------------------------------------------------------------------

data family TyFamily y z :: *

newtype instance TyFamily a b = TyFamily
    ( Id (FakeOut (Id a))
    , Id (FakeOut (Id b))
    , Id (Flip Either (Id a) (Id Int))
    , Id (Flip Either (Id b) (Id a))
    )
  deriving ( Arbitrary
           , Show
#if __GLASGOW_HASKELL__ >= 706
           , Generic
# if defined(__LANGUAGE_DERIVE_GENERIC1__)
           , Generic1
# endif
#endif
           )

-------------------------------------------------------------------------------

-- TODO: Replace these with non-orphan instances
$(deriveShow1 ''(,,,))
#if defined(NEW_FUNCTOR_CLASSES)
$(deriveShow2 ''(,,,))
#endif

$(deriveShow1 ''TyCon)
#if defined(NEW_FUNCTOR_CLASSES)
$(deriveShow2 ''TyCon)
#endif

$(deriveTextShow  ''TyCon)
$(deriveTextShow1 ''TyCon)
$(deriveTextShow2 ''TyCon)

#if !defined(NEW_FUNCTOR_CLASSES)
$(deriveShow1 'TyFamily)
#elif MIN_VERSION_template_haskell(2,7,0)
$(deriveShow1 'TyFamily)
$(deriveShow2 'TyFamily)
#else
instance Show a => Show1 (TyFamily a) where
    liftShowsPrec = liftShowsPrec2 showsPrec showList

instance Show2 TyFamily where
    liftShowsPrec2 sp1 sl1 sp2 sl2 p (TyFamily x) =
        showsTypeSynonym sp1 sl1 sp2 sl2 "TyFamily" p x

showsTypeSynonym :: (Int -> a -> ShowS) -> ([a] -> ShowS)
                 -> (Int -> b -> ShowS) -> ([b] -> ShowS)
                 -> String -> Int
                 -> ( Id (FakeOut (Id a))
                    , Id (FakeOut (Id b))
                    , Id (Flip Either (Id a) (Id Int))
                    , Id (Flip Either (Id b) (Id a))
                    )
                -> ShowS
showsTypeSynonym sp1 sl1 sp2 sl2 name p x =
    showsUnaryWith (liftShowsPrec2 (liftShowsPrec2 showsPrec showList sp1 sl1)
                                   (liftShowList2  showsPrec showList sp1 sl1)
                                   (liftShowsPrec2 sp1       sl1      sp2 sl2)
                                   (liftShowList2  sp1       sl1      sp2 sl2)
                   ) name p x
#endif

#if MIN_VERSION_template_haskell(2,7,0)
$(deriveTextShow  'TyFamily)
$(deriveTextShow1 'TyFamily)
$(deriveTextShow2 'TyFamily)
#endif

#if __GLASGOW_HASKELL__ < 706
$(Generics.deriveMeta           ''TyCon)
$(Generics.deriveRepresentable1 ''TyCon)
#endif

#if __GLASGOW_HASKELL__ < 702
$(Generics.deriveRepresentable0 ''TyCon)
#endif

#if MIN_VERSION_template_haskell(2,7,0)
# if !defined(__LANGUAGE_DERIVE_GENERIC1__)
$(Generics.deriveMeta           'TyFamily)
$(Generics.deriveRepresentable1 'TyFamily)
# endif

# if __GLASGOW_HASKELL__ < 706
$(Generics.deriveRepresentable0 'TyFamily)
# endif
#endif