Doaitse Swierstra wrote: > Just to show what kind of problems we are currently facing. The > following type checks in our EHC compiler and in Hugs, but not in the GHC: > > module Test where > > data T s = forall x. T (s -> (x -> s) -> (x, s, Int))
> > run :: (forall s . T s) -> Int > run ts = case ts of > T g -> let (x,_, b) = g x id > in b > > > Doaitse Swierstra > f :: Double -> (Char -> Double) -> (Char, Double, Int) f double charToDouble = (undefined, double, 0) t :: T Double t = T f -- And what will happen here: run t = ... The "id" in "T g = g _ id" tries to require that f :: Double -> (Double -> Double) -> (Double, Double, Int) but that is not correct. _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
