1 files changed, 37 insertions, 7 deletions
diff --git a/src/grasp.hs b/src/grasp.hs
index 4b12abd..fb8f866 100644
--- a/src/grasp.hs
+++ b/src/grasp.hs
@@ -1,27 +1,57 @@
 
-import System.Environment( getArgs )
+
+import qualified System.Environment as Env
+
+import System.Console.GetOpt( OptDescr )
+import qualified System.Console.GetOpt as GetOpt
+
 import Control.Exception( ErrorCall(..), Handler(..), catches )
+
+import qualified Control.Monad as Monad
+
 import Grasp.Parser
 import Grasp.Interpreter
 
 
 
 
+data Flag = Testing
+    deriving (Eq, Show)
+
+
+
+
 usageString :: String
-usageString = "Usage: grasp <program file>"
+usageString = "Usage: grasp [--testing] <program file>"
+
+
+
+options :: [OptDescr Flag]
+options =
+	[ GetOpt.Option ['t'] ["testing"] (GetOpt.NoArg Testing) "Enables before and after showing of program graph" ]
 
 
 
 program :: IO ()
 program = do
-    args <- getArgs
-    fileContents <- if (length args /= 1)
-                    then error usageString
-                    else readFile (head args)
+    (options, arguments, errors) <- Env.getArgs >>= return . GetOpt.getOpt GetOpt.Permute options
     
+    Monad.when (length options > 1) (error usageString)
+    Monad.when (length arguments /= 1) (error usageString)
+    Monad.when (length errors /= 0) (error usageString)
+
+    fileContents <- readFile (head arguments)
+
     case (parseGrasp fileContents) of
         Left x -> putStrLn (show x)
-        Right x -> grasp x >> return ()
+        Right x -> if (Testing `elem` options)
+        	        then do
+        	        	putStrLn "Input:"
+        	        	putStrLn (show x)
+        	        	y <- grasp x
+        	        	putStrLn "\nOutput:"
+        	        	putStrLn (show y)
+        	        else grasp x >> return ()