Sped up string decompression

DecompressString.hs

@@ -7,18 +7,14 @@ import System.FilePath (replaceFileName)
 
 decompressString :: String -> String
 decompressString s = go "" s where
-  go prev (x:xs) | Just word <- lookup (prev++[x]) dictionary = word ++ go "" xs
+  go prev (x:xs) | Just word <- Map.lookup (prev++[x]) dictionary = word ++ go "" xs
                  | otherwise                                      = go (prev++[x]) xs
   go _ [] = []
 
 
---dictionary :: Map.Map String String
---We need to read it at runtime, otherwise compilation is too slow and memory-hungry
---dictionary = Map.fromDistinctAscList $ map read $ lines listdict where
-dictionary :: [(String,String)]
-dictionary = map parse $lines listdict where
-    parse s | (first,tab:second) <- span (/='\t') s = (second,first)
-    listdict = unsafePerformIO $ getDict
+dictionary :: Map.Map String String
+dictionary = Map.fromDistinctAscList $ map splitTabs $ lines dict where
+    splitTabs s | (first,tab:second) <- span (/='\t') s = (first,second)
+    dict = unsafePerformIO $ getDict
     getDict = do
-              path <- getExecutablePath
-              readFile $ replaceFileName path "dictionary.tsv"
+              readFile $ "rdictionary.tsv"

compressString.hs

@@ -22,7 +22,7 @@ main = do args <- getArgs
               putStr $ unlines $ map quote results
             (_,_,errors) -> hPutStrLn stderr $ unlines errors ++ usageInfo "Usage: compressString [OPT] string" consoleOpts
        where
-         buildDict text = Map.fromList $ map splitTab $ lines text
+         buildDict text = Map.fromDistinctAscList $ map splitTab $ lines text
          splitTab s | (first,tab:second) <- span (/='\t') s = (first,second)
          quote s = '¨':s++"¨"
 
@@ -55,4 +55,4 @@ compressString opt s dictionary = go [(0, [""])] (map replaceNewlines s) where
   chooseBest (a@(_,[]):as)  (b:bs)         = b:chooseBest as bs   
   chooseBest (a@(l1,w1):as) (b@(l2,w2):bs) | l1 < l2             = a:chooseBest as bs
                                            | l1 ==l2 && not opt  = (l1,w1++w2):chooseBest as bs
-                                           | otherwise           = b:chooseBest as bs
+                                           | otherwise           = b:chooseBest as bs