Language/Symantic/Type/Tuple.hs

   1 {-# LANGUAGE FlexibleContexts #-}
   2 {-# LANGUAGE FlexibleInstances #-}
   3 {-# LANGUAGE PatternSynonyms #-}
   4 {-# LANGUAGE ScopedTypeVariables #-}
   5 {-# LANGUAGE TypeFamilies #-}
   6 {-# OPTIONS_GHC -fno-warn-orphans #-}
   7 module Language.Symantic.Type.Tuple where
   8
   9 import Data.Proxy
  10
  11 import Language.Symantic.Type.Common
  12
  13 -- * Type 'Type_Tuple2'
  14 -- | The (,) type.
  15 type Type_Tuple2
  16  = Type_Type2 Constraint2_Empty (,)
  17 pattern Type_Tuple2 arg res
  18  = Type_Type2 Proxy Proxy arg res
  19
  20 instance -- String_from_Type
  21  String_from_Type root =>
  22  String_from_Type (Type_Tuple2 root) where
  23         string_from_type (Type_Type2 _ _ a b) =
  24                 "("  ++ string_from_type a ++
  25                 ", " ++ string_from_type b ++ ")"
  26
  27 -- | Convenient alias to include a 'Type_Tuple2' within a type.
  28 type_tuple2
  29  :: forall root h_a h_b.
  30  Lift_Type_Root Type_Tuple2 root
  31  => root h_a
  32  -> root h_b
  33  -> root (h_a, h_b)
  34 type_tuple2 a b = lift_type_root (Type_Tuple2 a b
  35          ::Type_Tuple2 root (h_a, h_b))