{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE PatternSynonyms #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeFamilies #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
module Language.Symantic.Type.Unit where

import qualified Data.MonoTraversable as MT
import Data.Proxy

import Language.Symantic.Type.Root
import Language.Symantic.Type.Type0
import Language.Symantic.Type.Constraint
import Language.Symantic.Type.Family

-- * Type 'Type_Unit'
-- | The @()@ type.
type Type_Unit = Type0 (Proxy ())

pattern Type_Unit :: Type_Unit root ()
pattern Type_Unit = Type0 Proxy

instance Type0_Constraint Eq (Type_Unit root) where
	type0_constraint _c Type0{} = Just Dict
instance Type0_Constraint Ord (Type_Unit root) where
	type0_constraint _c Type0{} = Just Dict
instance Type0_Constraint Monoid (Type_Unit root)
instance Type0_Constraint Num (Type_Unit root)
instance Type0_Constraint Integral (Type_Unit root)
instance Type0_Family Type_Family_MonoElement (Type_Unit root)
instance Type0_Constraint MT.MonoFunctor (Type_Unit root)
instance String_from_Type (Type_Unit root) where
	string_from_type _ = "()"

-- | Inject 'Type_Unit' within a root type.
type_unit :: Type_Root_Lift Type_Unit root => root ()
type_unit = type0