Language/Symantic/Type/List.hs

   1 {-# LANGUAGE FlexibleContexts #-}
   2 {-# LANGUAGE FlexibleInstances #-}
   3 {-# LANGUAGE MultiParamTypeClasses #-}
   4 {-# LANGUAGE PatternSynonyms #-}
   5 {-# LANGUAGE TypeFamilies #-}
   6 {-# OPTIONS_GHC -fno-warn-orphans #-}
   7 module Language.Symantic.Type.List where
   8
   9 import Data.Proxy
  10 import Data.Type.Equality ((:~:)(Refl))
  11 import Language.Symantic.Type.Root
  12 import Language.Symantic.Type.Type0
  13 import Language.Symantic.Type.Type1
  14
  15 -- * Type 'Type_List'
  16 -- | The list type.
  17 type Type_List = Type_Type1 (Proxy [])
  18
  19 pattern Type_List :: root a -> Type_List root ([] a)
  20 pattern Type_List a = Type_Type1 Proxy a
  21
  22 instance Constraint_Type Eq root => Constraint_Type Eq (Type_List root) where
  23         constraint_type c (Type_Type1 _ a)
  24          | Just Dict <- constraint_type c a
  25          = Just Dict
  26         constraint_type _c _ = Nothing
  27 instance Constraint_Type Ord root => Constraint_Type Ord (Type_List root) where
  28         constraint_type c (Type_Type1 _ a)
  29          | Just Dict <- constraint_type c a
  30          = Just Dict
  31         constraint_type _c _ = Nothing
  32 instance Constraint_Type Monoid (Type_List root) where
  33         constraint_type _c Type_Type1{} = Just Dict
  34 instance Constraint_Type1 Functor (Type_List root) where
  35         constraint_type1 _c Type_Type1{} = Just Dict
  36 instance Constraint_Type1 Applicative (Type_List root) where
  37         constraint_type1 _c Type_Type1{} = Just Dict
  38 instance Constraint_Type1 Foldable (Type_List root) where
  39         constraint_type1 _c Type_Type1{} = Just Dict
  40 instance Constraint_Type1 Traversable (Type_List root) where
  41         constraint_type1 _c Type_Type1{} = Just Dict
  42 instance Constraint_Type1 Monad (Type_List root) where
  43         constraint_type1 _c Type_Type1{} = Just Dict
  44 instance -- Eq_Type
  45  Eq_Type root =>
  46  Eq_Type (Type_List root) where
  47         eq_type (Type_Type1 _px1 a1) (Type_Type1 _px2 a2)
  48          | Just Refl <- a1 `eq_type` a2
  49          = Just Refl
  50         eq_type _ _ = Nothing
  51 instance -- Eq_Type1
  52  Eq_Type1 (Type_List root) where
  53         eq_type1 Type_Type1{} Type_Type1{}
  54          = Just Refl
  55 instance -- String_from_Type
  56  String_from_Type root =>
  57  String_from_Type (Type_List root) where
  58         string_from_type (Type_Type1 _f a) =
  59                 "[" ++ string_from_type a ++ "]"
  60
  61 -- | Inject 'Type_List' within a root type.
  62 type_list
  63  :: Lift_Type_Root Type_List root
  64  => root h_a
  65  -> root ([] h_a)
  66 type_list = lift_type_root . Type_Type1 (Proxy::Proxy [])