> Luckily, there is a workaround (discovered by Tom Moertel on
> #haskell). If you include field names in the data
> definition for which you derive Show and Read, it seems to
> work fine.
>
> So, in George's example
>
> module GHCBug where
>
> data Command =
> NewLocation
> | Commit {a :: Int, b :: String, c :: (Maybe String)}
> | Retrieve String String
> | ListVersions String
> deriving (Read,Show)
>
> should be all that is needed.
>
> It seems that as soon as the value of the Maybe type is
> delimited by a punctuation symbol or bracket, all is fine.
Thanks. I've added a note to the download page for 5.04.1 about this
bug.
Given that there's a workaround, we won't do 5.04.2 immediately but
we'll certainly move along to 5.04.2 quicker than we would have
otherwise.
Cheers,
Simon
_______________________________________________
Glasgow-haskell-bugs mailing list
[EMAIL PROTECTED]
http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
