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diff --git a/src/Codec/Binary/Url.hs b/src/Codec/Binary/Url.hs
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+-- |
+-- Module    : Codec.Binary.Url
+-- Copyright : (c) 2009 Magnus Therning
+-- License   : BSD3
+--
+-- URL encoding, sometimes referred to as URI encoding or percent encoding.
+-- Implemented based on RFC 3986 (<http://tools.ietf.org/html/rfc3986>).
+--
+-- Further documentation and information can be found at
+-- <http://www.haskell.org/haskellwiki/Library/Data_encoding>.
+
+module Codec.Binary.Url
+    ( EncIncData(..)
+    , EncIncRes(..)
+    , encodeInc
+    , encode
+    , DecIncData
+    , DecIncRes
+    , decodeInc
+    , decode
+    , chop
+    , unchop
+    ) where
+
+import Codec.Binary.Util
+
+import qualified Data.Map as M
+import Data.Char(ord)
+import Data.Word(Word8)
+import Data.Maybe(isJust, fromJust)
+
+-- {{{1 enc/dec map
+_unreservedChars = zip [65..90] "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+        ++ zip [97..122] "abcdefghijklmnopqrstuvwxyz"
+        ++ zip [48..57] "0123456789"
+        ++ [(45, '-'), (95, '_'), (46, '.'), (126, '~')]
+
+encodeMap :: M.Map Word8 Char
+encodeMap = M.fromList _unreservedChars
+
+decodeMap :: M.Map Char Word8
+decodeMap = M.fromList [(b, a) | (a, b) <- _unreservedChars]
+
+-- {{{1 encode
+-- | Incremental decoder function.
+encodeInc :: EncIncData -> EncIncRes String
+encodeInc e = eI e
+    where
+        enc [] = []
+        enc (o : os) = case (M.lookup o encodeMap) of
+            Just c -> c : enc os
+            Nothing -> ('%' : toHex o) ++ enc os
+
+        eI EDone = EFinal []
+        eI (EChunk bs) = EPart (enc bs) encodeInc
+
+-- | Encode data.
+encode :: [Word8] -> String
+encode = encoder encodeInc
+
+-- {{{1 decode
+-- | Incremental decoder function.
+decodeInc :: DecIncData String -> DecIncRes String
+decodeInc d = dI [] d
+    where
+        dI [] DDone = DFinal [] []
+        dI lo DDone = DFail [] lo
+        dI lo (DChunk s) = doDec [] (lo ++ s)
+            where
+                doDec acc [] = DPart acc (dI [])
+                doDec acc s'@('%':c0:c1:cs) = let
+                        o = fromHex [c0, c1]
+                    in if isJust o
+                        then doDec (acc ++ [fromJust o]) cs
+                        else DFail acc s'
+                doDec acc s'@(c:cs)
+                    | c /= '%' = doDec (acc ++ [fromIntegral $ ord c]) cs
+                    | otherwise = DPart acc (dI s')
+
+-- | Decode data.
+decode :: String
+    -> Maybe [Word8]
+decode = decoder decodeInc
+
+-- {{{1 chop
+-- | Chop up a string in parts.
+chop :: Int     -- ^ length of individual lines
+    -> String
+    -> [String]
+chop n = let
+        _n = max 1 n
+        _chop [] = []
+        _chop cs = take _n cs : _chop (drop _n cs)
+    in _chop
+
+-- {{{1 unchop
+-- | Concatenate the strings into one long string
+unchop :: [String]
+    -> String
+unchop = foldr (++) ""