29 Jun
2002
29 Jun
'02
4:16 p.m.
Hello.
Can I write dependencies like this:
class C x y z | x -> (y, z) class D x y z | (x, y) -> z
in hugs? in ghc? The ghc doc refers to Mark Jones: "Type Classes with Functional Dependencies", http://www.cse.ogi.edu/~mpj/pubs/fundeps.html where this seems to be allowed (section 4, page 9)
Especially, I would need class D above.
class C can be rewritten to
class C x y z | x -> y, x -> z
concerning class D, I used (in GHC)
class D x y z | x y -> z
and it seemed to do what I wanted. I guess
class C x y z | x -> y z
would work too. Zdenek Dvorak _________________________________________________________________ MSN Photos is the easiest way to share and print your photos: http://photos.msn.com/support/worldwide.aspx