On Wed, Jan 2, 2013 at 11:20 AM, Dan Doel <[email protected]> wrote:
> Note that even left-to-right behavior covers all cases, as you might have: > > f x y > > such that y requires x to be checked polymorphically in the same way. > There are algorithms that can get this right in general, but it's a little > tricky, and they're rather different than GHC's algorithm, so I don't know > whether it's possible to make GHC behave correctly. > Oops, that should have been, "note that not even left-to-right behavior covers all cases." Also, I don't mean to imply that GHC is behaving wrongly. Situations like these are usually the result of necessary trade-offs in the algorithms. GHC does a lot of things that algorithms that successfully check this type of examples don't have to deal with at all. You have to pick your poison. -- Dan
_______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
