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--- $Id: Bit.hs#1 2009/10/01 10:31:09 REDMOND\\satnams $
-------------------------------------------------------------------------------

module Lava.Bit
where

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data Bit = One | Zero
           deriving Eq

-------------------------------------------------------------------------------

instance Show Bit where
  showsPrec _ Zero = showString "0"
  showsPrec _ One  = showString "1"

-------------------------------------------------------------------------------

instance Num Bit where
  fromInteger 0 = Zero
  fromInteger 1 = One
  (+) = undefined
  (*) = undefined
  abs = undefined
  signum = undefined

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fromBit :: Bit -> Bool
fromBit Zero = False
fromBit One  = True

-------------------------------------------------------------------------------

toBit :: Bool -> Bit
toBit False = Zero
toBit True = One

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unaryBoolToBit :: (Bool -> Bool) -> (Bit -> Bit)
unaryBoolToBit f bit = toBit (f (fromBit bit))

-------------------------------------------------------------------------------

binaryBoolToBit :: (Bool -> Bool -> Bool) -> (Bit -> Bit -> Bit)
binaryBoolToBit f bit1 bit2
  = toBit (f (fromBit bit1) (fromBit bit2))

-------------------------------------------------------------------------------

f3BoolToBit :: (Bool -> Bool -> Bool -> Bool) -> (Bit -> Bit -> Bit -> Bit)
f3BoolToBit f bit1 bit2 bit3
  = toBit (f (fromBit bit1) (fromBit bit2)(fromBit bit3))

-------------------------------------------------------------------------------

f4BoolToBit :: (Bool -> Bool -> Bool -> Bool -> Bool) -> 
               (Bit -> Bit -> Bit -> Bit -> Bit)
f4BoolToBit f bit1 bit2 bit3 bit4
  = toBit (f (fromBit bit1) (fromBit bit2)(fromBit bit3) (fromBit bit4))

-------------------------------------------------------------------------------