{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE NoImplicitPrelude #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE UndecidableInstances #-}
-- | Interpreter to duplicate the representation of an expression
-- in order to evaluate it with different interpreters.
--
-- NOTE: this is a more verbose, less clear,
-- and maybe less efficient alternative
-- to maintaining the universal polymorphism of @repr@ at parsing time
-- as done with 'Forall_Repr_with_Context';
-- it is mainly here for the sake of curiosity.
module Language.Symantic.Repr.Dup where

-- | Interpreter's data.
data Dup repr1 repr2 a
 =   Dup
 {   dup1 :: repr1 a
 ,   dup2 :: repr2 a
 }