cli/Hcompta/Expr/Set.hs

   1 {-# LANGUAGE NoImplicitPrelude #-}
   2 {-# OPTIONS_GHC -fno-warn-tabs #-}
   3
   4 module Hcompta.Expr.Set where
   5
   6 import Hcompta.Expr.Dup
   7
   8 -- * Class 'Expr_Set'
   9
  10 class Expr_Set repr where
  11         complement   :: repr a -> repr a
  12         intersection :: repr a -> repr a -> repr a
  13         union        :: repr a -> repr a -> repr a
  14
  15 instance -- Expr_Set Dup
  16  ( Expr_Set r1
  17  , Expr_Set r2
  18  ) => Expr_Set (Dup r1 r2) where
  19         complement (x1 `Dup` x2) = complement x1 `Dup` complement x2
  20         intersection (x1 `Dup` x2) (y1 `Dup` y2) = intersection x1 y1 `Dup` intersection x2 y2
  21         union  (x1 `Dup` x2) (y1 `Dup` y2) = union  x1 y1 `Dup` union  x2 y2