cli/Hcompta/Expr/Dup.hs

   1 {-# LANGUAGE NoImplicitPrelude #-}
   2 {-# OPTIONS_GHC -fno-warn-tabs #-}
   3
   4 module Hcompta.Expr.Dup where
   5
   6 -- | Data type to duplicate an expression
   7 -- in order to evaluate it with different interpreters.
   8 data Dup repr1 repr2 a
   9  =   Dup
  10  {   dup1 :: repr1 a
  11  ,   dup2 :: repr2 a
  12  }
  13
  14
  15 {-
  16 -- * Whenever we use a value, we have to duplicate it first,
  17 -- to leave the other copy for different interpreters
  18 dup_consume ev x =
  19         print (ev x1) >> return x2
  20         where (x1, x2) = duplicate x
  21 -}