[Haskell-cafe] Read Instance code.

Andy Stewart lazycat.manatee at gmail.com
Sat Jul 3 07:22:39 EDT 2010

Hi all,

I have some incorrect "Read instance" make i got error "Prelude.read: no
parse", and i don't know how to fix it. 

------------------------------> code start <------------------------------
newtype SerializedWindow = SerializedWindow (Maybe DrawWindow)
instance Show SerializedWindow where    
  show _ = "SerializedWindow Nothing"
instance Read SerializedWindow where           
    readsPrec _ str = [(SerializedWindow Nothing, idStr) 
                           | (val :: String, idStr) <- reads str]
------------------------------> code end   <------------------------------
Any help?


  -- Andy

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