Language/Symantic/Repr/Dup.hs

   1 {-# LANGUAGE FlexibleContexts #-}
   2 {-# LANGUAGE FlexibleInstances #-}
   3 {-# LANGUAGE MultiParamTypeClasses #-}
   4 {-# LANGUAGE NoImplicitPrelude #-}
   5 {-# LANGUAGE TypeFamilies #-}
   6 {-# LANGUAGE UndecidableInstances #-}
   7 -- | Interpreter to duplicate the representation of an expression
   8 -- in order to evaluate it with different interpreters.
   9 --
  10 -- NOTE: this is a more verbose, less clear,
  11 -- and maybe less efficient alternative
  12 -- to maintaining the universal polymorphism of @repr@ at parsing time
  13 -- as done with 'Forall_Repr_with_Context';
  14 -- it is mainly here for the sake of curiosity.
  15 module Language.Symantic.Repr.Dup where
  16
  17 -- | Interpreter's data.
  18 data Dup repr1 repr2 a
  19  =   Dup
  20  {   dup1 :: repr1 a
  21  ,   dup2 :: repr2 a
  22  }