Hi,
In some Haskell code I am writing at the moment I use a number of
multi-parameter classes, with various interrelated instances. One class
looks like
class Convert from to where conv :: from - to
Everything works fine, but when I add functional dependencies, to reduce
the need for
"Jeffrey R. Lewis" wrote:
I'll certainly have a look, but, Thomas, I'll need more to go on. Also, I
wouldn't count on much from the implementation of functional dependencies
in 4.08 - it was only partially implemented at the time that release was
snapshotted.
I'll try to construct a
On the page
http://www.haskell.org/ghc/download.html
The link titled "RedHat 7 binary" should be changed
from this URL:
ftp://ftp.cse.unsw.edu.au/pub/users/chak/jibunmaki/i386/ghc-4.08.1-1.i386.rpm
to this URL:
ftp://ftp.cse.unsw.edu.au/pub/users/chak/jibunmaki/i386/ghc-4.08.1-2.i386.rpm
"Jeffrey R. Lewis" wrote:
I'll certainly have a look, but, Thomas, I'll need more to go on. Also, I wouldn't
count on much from the implementation of functional dependencies in 4.08 - it was
only partially implemented at the time that release was snapshotted.
--Jeff
Simon Peyton-Jones
Hi,
Here is another example which GHC doesn't like.
Regards,
Thomas Hallgren
module PR where
-- This accepted by Hugs, but not by GHC 4.08.1
class P a
class R a b | b-a
instance (P a,R a b) = P b
{-
GHC 4.08.1
