made a JSON instance for Rev

Author: Martin Hilbig

src/Database/CouchDB.hs

@@ -87,6 +87,12 @@ data Rev = Rev { unRev :: JSString } deriving (Eq,Ord)
 instance Show Rev where
  show (Rev s) = fromJSString s
 
+instance JSON Rev where
+ readJSON (JSString s) = return (Rev s)
+ readJSON _ = fail "readJSON: not a valid document revision"
+
+ showJSON (Rev s) = showJSON s
+
 -- |Document name
 data Doc = Doc { unDoc :: JSString } deriving (Eq,Ord)