deriving over renamed types

[Simon Peyton-Jones]

It's a bug in GHC 5.02 and earlier; fixed in 5.03

Simon

| -----Original Message-----
| From: Hal Daume III [mailto:hdaume@ISI.EDU]=20
| Sent: 04 April 2002 00:15
| To: Haskell Mailing List
| Subject: deriving over renamed types
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| Why can't I do this:
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| > import FiniteMap
| > type FM =3D FiniteMap
| > instance (Show a, Show b) =3D> Show (FiniteMap a b) where
| >     show =3D show . fmToList
| > data X =3D X (FM Int Int)
| >        deriving (Show)
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| if I replace
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| > type FM =3D FiniteMap
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| with
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| > type FM a b =3D FiniteMap a b
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| it works fine.  I wasn't aware there was (supposed to be) a=20
| difference between these two declarations?  Is there?
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|  - Hal
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| --
| Hal Daume III
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|  "Computer science is no more about computers    | hdaume@isi.edu
|   than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume
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