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diff --git a/src/Text/Pandoc/UUID.hs b/src/Text/Pandoc/UUID.hs
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+{-
+Copyright (C) 2010 John MacFarlane <jgm@berkeley.edu>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+-}
+
+{- |
+   Module      : Text.Pandoc.UUID
+   Copyright   : Copyright (C) 2010 John MacFarlane
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : John MacFarlane <jgm@berkeley.edu>
+   Stability   : alpha
+   Portability : portable
+
+UUID generation using Version 4 (random method) described
+in RFC4122. See http://tools.ietf.org/html/rfc4122
+-}
+
+module Text.Pandoc.UUID ( UUID, getRandomUUID ) where
+
+import Text.Printf ( printf )
+import System.Random ( randomIO )
+import Data.Word
+import Data.Bits ( setBit, clearBit )
+import Control.Monad ( liftM )
+
+data UUID = UUID Word8 Word8 Word8 Word8 Word8 Word8 Word8 Word8
+                 Word8 Word8 Word8 Word8 Word8 Word8 Word8 Word8
+
+instance Show UUID where
+  show (UUID a b c d e f g h i j k l m n o p) =
+   "urn:uuid:" ++
+   printf "%02x" a ++
+   printf "%02x" b ++
+   printf "%02x" c ++
+   printf "%02x" d ++
+   "-" ++
+   printf "%02x" e ++
+   printf "%02x" f ++
+   "-" ++
+   printf "%02x" g ++
+   printf "%02x" h ++
+   "-" ++
+   printf "%02x" i ++
+   printf "%02x" j ++
+   "-" ++
+   printf "%02x" k ++
+   printf "%02x" l ++
+   printf "%02x" m ++
+   printf "%02x" n ++
+   printf "%02x" o ++
+   printf "%02x" p
+
+getRandomUUID :: IO UUID
+getRandomUUID = do
+  let getRN :: a -> IO Word8
+      getRN _ = liftM fromIntegral (randomIO :: IO Int)
+  [a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p] <- mapM getRN ([1..16] :: [Int])
+  -- set variant
+  let i' = i `setBit` 7 `clearBit` 6
+  -- set version (0100 for random)
+  let g' = g `clearBit` 7 `setBit` 6 `clearBit` 5 `clearBit` 4
+  return $ UUID a b c d e f g' h i' j k l m n o p
+