src/Bit.hs

   1 module Bit where
   2
   3 data Bit = None | Zero | One
   4          deriving (Eq, Show)
   5
   6 bit_to_int :: Bit -> Int
   7 bit_to_int None = -1
   8 bit_to_int Zero =  0
   9 bit_to_int One  =  1
  10
  11 -- If we are passed a '0' or '1', convert it appropriately. Otherwise,
  12 -- default to None.
  13 bit_from_char :: Char -> Bit
  14 bit_from_char '0' = Zero
  15 bit_from_char '1' = One
  16 bit_from_char  _  = None