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Generics
by Simon Peyton-Jones 05 Oct '00

05 Oct '00

Folks, I've added Hinze/PJ-style generic class definitions to GHC, based on summer hacking done by Andrei Serjantov. The design is based very closely on the Haskell workshop 2000 paper http://www.informatik.uni-bonn.de/~ralf/Derive.ps.gz For example: class Bin a where toBin :: a -> [Int] fromBin :: [Int] -> (a, [Int]) toBin {| Unit |} Unit = [] toBin {| a :+: b |} (Inl x) = 0 : toBin x toBin {| a :+: b |} (Inr y) = 1 : toBin y toBin {| a :*: b |} (x :*: y) = toBin x ++ toBin y fromBin {| Unit |} bs = (Unit, bs) fromBin {| a :+: b |} (0:bs) = (Inl x, bs') where (x,bs') = fromBin bs fromBin {| a :+: b |} (1:bs) = (Inr y, bs') where (y,bs') = fromBin bs fromBin {| a :*: b |} bs = (x :*: y, bs'') where (x,bs' ) = fromBin bs (y,bs'') = fromBin bs' Now we can say simply instance Bin a => Bin [a] and the compiler will derive the appropriate code automatically. This is now implemented and documented in the CVS version of GHC, and will be in every future version of GHC. (But I'm afraid we don't plan a binary release for a while.) At present we don't (alas) support constructor and field names, so you can't implement Read and Show generically. But I thought it was worth getting committed what *is* done. Simon

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New InstallShield of GHC 4.08.1
by Reuben Thomas 04 Oct '00

04 Oct '00

I've just put up a new InstallShield of 4.08.1 (http://www.haskell.org/ghc/download.html, as usual). It fixes some problems with missing symbols when linking dynamically, and is also better behaved, in that it clears up the temporary files it makes during installation, so that when uninstalled it really does delete everything. -- http://sc3d.org/rrt/ | maxim, n. wisdom for fools

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Astromerkez'den Fenerbah�e-Be�ikta� derbisinin sonucu...
by Astromerkez 02 Feb '00

02 Feb '00

1 0

slm
by zeynep 03 Apr '83

03 Apr '83

1 0

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