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diff --git a/Utility/JSONStream.hs b/Utility/JSONStream.hs
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+{- Streaming JSON output.
+ -
+ - Copyright 2011 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Utility.JSONStream (
+	start,
+	add,
+	end
+) where
+
+import Text.JSON
+
+{- Text.JSON does not support building up a larger JSON document piece by
+   piece as a stream. To support streaming, a hack. The JSObject is converted
+   to a string with its final "}" is left off, allowing it to be added to
+   later. -}
+start :: JSON a => [(String, a)] -> String
+start l
+	| last s == endchar = take (length s - 1)  s
+	| otherwise = bad s
+	where
+		s = encodeStrict $ toJSObject l
+
+add :: JSON a => [(String, a)] -> String
+add l
+	| head s == startchar = ',' : drop 1 s
+	| otherwise = bad s
+	where
+		s = start l
+
+end :: String
+end = [endchar, '\n']
+
+startchar :: Char
+startchar = '{'
+
+endchar :: Char
+endchar = '}'
+
+bad :: String -> a
+bad s = error $ "Text.JSON returned unexpected string: " ++ s