benchmark, test suite, and run length encoding

bench/Bench.hs

@@ -0,0 +1,15 @@
+import Criterion.Main
+import Compress.LengthDistancePairs
+import qualified Data.ByteString as BS
+import qualified Compress.Arithmetic as A
+
+main = do
+  testData <- BS.unpack . BS.take 10000 <$> (BS.readFile "pg64317.txt")
+  defaultMain [
+        bgroup "encode" [
+                bench "length distance pair" $ nf (encode :: [Word8] -> [LengthDistancePair Word32]) testData
+                                ],
+        bgroup "arithmetic coding" [
+                bench "pg64317.txt" $ nf A.compress testData
+                                ]
+                   ]