> one should be able to define two instances having the same signature, as > long as they are in different namespaces [snip] > But now, ghc complains about two instances of Foo Integer, although > there should be none in the namespace main.
It's a Haskell problem, not a ghc one. Class instances are not constrained by module boundaries. Other people have found this to be a problem, e.g. in combination with tools like Strafunski - you just cannot encapsulate a class instance in a module. It's a design flaw in Haskell. > I have not found any documentation on why ghc behaves like this and > whether this conforms to the haskell language specification. > Is there any haskell compiler out there that is able to compile the > above example? I think Clean (a very similar language) permits to limit the scope of class instances. Stefan _______________________________________________ Haskell mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell
