RE: Auto generated instance codes through 'deriving'

The following code snippet not works correctly.
data Obj = Obj {_id, p1, p2::Int} deriving (Show, Read)
showObj :: Obj -> String
showObj o = show o
main = do print (showObj (read "Obj {_id=1,p1=10,p2=20}"))
return ()
The reason is because I used the property name with underscore char like "_id". Looking into auto generated class codes and seeing they show it should encompass identifiers with special characters with parenthesis, so I tried "Obj {(_id)=1,p1=10,p2=20}" as argument of read func. But, the result is same, parse error. Is this problem by-design or bug? Or Am I missing any point? Thanks, /JongKeun -----Original Message----- From: Simon Peyton-Jones Sent: Friday, February 07, 2003 5:41 PM To: Jong Keun Na; haskell-cafe@haskell.org Subject: RE: Auto generated instance codes through 'deriving' Try -ddump-deriv http://haskell.cs.yale.edu/ghc/docs/latest/html/users_guide/options-debu gging.html#DUMPING-OUTPUT Simon -----Original Message----- From: Jong Keun Na [mailto:jongkn@microsoft.com] Sent: 07 February 2003 06:15 To: haskell-cafe@haskell.org Subject: Auto generated instance codes through 'deriving' Hello folks, Is there any method with which I can see instance's codes generated automatically by using 'deriving' keyword in GHC? I'm curious in how GHC generates 'Read' class's instance code for user-defined data type. Any help will be great appreciated. /JongKeun
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Jong Keun Na