Added Template Haskell helper functions

darcs-hash:20070823120526-a4fee-4d3fcf18768f5be81a81309d003f991c269ca136

Data/Encoding/Helper/Template.hs

@@ -0,0 +1,33 @@
+{- This module is used to create arrays from lists in template haskell -}
+
+module Data.Encoding.Helper.Template where
+
+import Data.Char
+import Data.Word
+import Data.Array.IArray (Array,array)
+import Language.Haskell.TH
+
+createCharArray :: [(Integer,Char)] -> Integer -> Integer -> Q Exp
+#ifndef __HADDOCK__
+createCharArray lst = createArray (map (\(x,y) -> (x,LitE $ CharL y)) lst)
+#endif
+
+createArray :: [(Integer,Exp)] -> Integer -> Integer -> Q Exp
+#ifndef __HADDOCK__
+createArray lst from to = return $ AppE
+	(AppE
+		(VarE 'array)
+		(TupE [LitE $ IntegerL from,LitE $ IntegerL to]))
+	(ListE [ TupE [LitE $ IntegerL x,y]
+		| (x,y) <- lst ])
+#endif
+
+xmlArray :: [(Char,[Word8])] -> Integer -> Integer -> Q Exp
+#ifndef __HADDOCK__
+xmlArray lst l u = do
+	let trans = map (\(ch,bin) ->
+		(toInteger $ ord ch
+		,TupE [LitE $ IntegerL (toInteger $ length bin),TupE $ map (\b -> LitE $ IntegerL (fromIntegral b)) bin ++ replicate (4-length bin) (LitE $ IntegerL 0)]
+		)) (filter (\(c,_) -> ord c <= fromInteger u && ord c >= fromInteger l) lst)
+	createArray trans l u
+#endif