src/Maskbits.hs

   1 module Maskbits(
   2   Maskbits(..),
   3   )
   4 where
   5
   6 import Test.QuickCheck (Arbitrary(..), elements)
   7
   8
   9 -- | A type representing the number of bits in a CIDR netmask.
  10 data Maskbits =
  11     Zero
  12   | One
  13   | Two
  14   | Three
  15   | Four
  16   | Five
  17   | Six
  18   | Seven
  19   | Eight
  20   | Nine
  21   | Ten
  22   | Eleven
  23   | Twelve
  24   | Thirteen
  25   | Fourteen
  26   | Fifteen
  27   | Sixteen
  28   | Seventeen
  29   | Eighteen
  30   | Nineteen
  31   | Twenty
  32   | TwentyOne
  33   | TwentyTwo
  34   | TwentyThree
  35   | TwentyFour
  36   | TwentyFive
  37   | TwentySix
  38   | TwentySeven
  39   | TwentyEight
  40   | TwentyNine
  41   | Thirty
  42   | ThirtyOne
  43   | ThirtyTwo
  44     deriving (Enum, Eq, Ord)
  45
  46
  47 instance Show Maskbits where
  48   show Zero        = "0"
  49   show One         = "1"
  50   show Two         = "2"
  51   show Three       = "3"
  52   show Four        = "4"
  53   show Five        = "5"
  54   show Six         = "6"
  55   show Seven       = "7"
  56   show Eight       = "8"
  57   show Nine        = "9"
  58   show Ten         = "10"
  59   show Eleven      = "11"
  60   show Twelve      = "12"
  61   show Thirteen    = "13"
  62   show Fourteen    = "14"
  63   show Fifteen     = "15"
  64   show Sixteen     = "16"
  65   show Seventeen   = "17"
  66   show Eighteen    = "18"
  67   show Nineteen    = "19"
  68   show Twenty      = "20"
  69   show TwentyOne   = "21"
  70   show TwentyTwo   = "22"
  71   show TwentyThree = "23"
  72   show TwentyFour  = "24"
  73   show TwentyFive  = "25"
  74   show TwentySix   = "26"
  75   show TwentySeven = "27"
  76   show TwentyEight = "28"
  77   show TwentyNine  = "29"
  78   show Thirty      = "30"
  79   show ThirtyOne   = "31"
  80   show ThirtyTwo   = "32"
  81
  82
  83 instance Arbitrary Maskbits where
  84   arbitrary =
  85     elements [ Zero,
  86                One,
  87                Two,
  88                Three,
  89                Four,
  90                Five,
  91                Six,
  92                Seven,
  93                Eight,
  94                Nine,
  95                Ten,
  96                Eleven,
  97                Twelve,
  98                Thirteen,
  99                Fourteen,
 100                Fifteen,
 101                Sixteen,
 102                Seventeen,
 103                Eighteen,
 104                Nineteen,
 105                Twenty,
 106                TwentyOne,
 107                TwentyTwo,
 108                TwentyThree,
 109                TwentyFour,
 110                TwentyFive,
 111                TwentySix,
 112                TwentySeven,
 113                TwentyEight,
 114                TwentyNine,
 115                Thirty,
 116                ThirtyOne,
 117                ThirtyTwo ]
 118
 119
 120 instance Read Maskbits where
 121   readsPrec _ s =
 122     case (reads s :: [(Int, String)]) of
 123       []              -> []
 124       (x,leftover):_  -> go x leftover
 125     where
 126       go :: Int -> String -> [(Maskbits, String)]
 127       go x' leftover'
 128         | x' < minBound || x' > maxBound = []
 129         | otherwise = [(toEnum x', leftover')]