Update for QuickCheck 2.

[hath.git] / src / Bit.hs

diff --git a/src/Bit.hs b/src/Bit.hs
index 7c1840823b041774774f7d49519ff190f6f52033..a4241bc2a72b8a062649def5d1daa40f0a13f030 100644 (file)
--- a/src/Bit.hs
+++ b/src/Bit.hs
@@ -1,7 +1,20 @@
 module Bit where
 
+import Test.QuickCheck
+
+
 data Bit = None | Zero | One
-         deriving (Eq, Show)
+         deriving (Eq)
+
+instance Show Bit where
+    show None = "None"
+    show Zero = "0"
+    show One  = "1"
+
+
+instance Arbitrary Bit where
+    arbitrary = elements [ Zero, One ]
+
 
 bit_to_int :: Bit -> Int
 bit_to_int None = -1