module Octet where
+import Test.HUnit
+
import Bit
-- An Octet consists of eight bits. For our purposes, the most
b6 :: Bit,
b7 :: Bit,
b8 :: Bit }
- deriving (Eq, Show)
+ deriving (Eq)
+
+
+instance Show Octet where
+ show Octet.None = "None"
+ show oct = show (octet_to_int oct)
+
-- Convert each bit to its integer value, and multiply by the
-- appropriate power of two. Sum them up, and we should get an integer
| (x < 0) || (x > 255) = Octet.None
| otherwise = (Octet a1 a2 a3 a4 a5 a6 a7 a8)
where
- a1 = if (x > 128) then One else Zero
+ a1 = if (x >= 128) then One else Zero
a2 = if ((x `mod` 128) >= 64) then One else Zero
a3 = if ((x `mod` 64) >= 32) then One else Zero
a4 = if ((x `mod` 32) >= 16) then One else Zero
-- The octet with the greatest possible value.
max_octet :: Octet
max_octet = Octet One One One One One One One One
+
+
+
+-- HUnit Tests
+test_octet_from_int1 :: Test
+test_octet_from_int1 =
+ TestCase $ assertEqual "octet_from_int 128 should parse as 10000000" oct1 (octet_from_int 128)
+ where
+ oct1 = Octet One Zero Zero Zero Zero Zero Zero Zero
+
+
+octet_tests :: [Test]
+octet_tests = [ test_octet_from_int1 ]