Getting a [(String, TypeRep)] from a Configuration object

app/MyGetOpt.hs

@@ -0,0 +1,28 @@
+{-# LANGUAGE DeriveDataTypeable #-}
+
+import Data.Data
+import Data.Typeable
+
+
+data Configuration = Configuration {
+  rule :: Int,
+  start :: Maybe Int,
+  lines :: Maybe Int,
+  window :: Maybe Int,
+  move :: Maybe Int
+} deriving (Show, Data, Typeable)
+
+argsName :: [String]
+argsName = constrFields . head . dataTypeConstrs  $ dataTypeOf (undefined :: Configuration)
+
+argsType :: [TypeRep]
+argsType = recurse $ typeOf Configuration
+  where recurse x = let (_, y) = splitTyConApp x in
+                    case y of (z:zs:[]) -> z : recurse zs
+                              []        -> []
+
+args :: [(String, TypeRep)]
+args = zip argsName argsType
+
+--getOpt :: [String] -> Configuration
+--getOpt [] ->