>> what about these? >> f,g :: Bool -> Int >> f x = 6 >> g x = x `seq` 6 > > As pointed out on #haskell by roconnor, we apparently don't care, this is a > shame... We only care that x == y => f x == g y, and x == y can't tell if > _|_ == _|_.
So the facts that (1) f == g (2) f undefined = 6 (3) g undefined = undefined is not a problem? /Jonas 2010/4/14 Thomas Davie <tom.da...@gmail.com>: > > On 14 Apr 2010, at 09:12, Jonas Almström Duregård wrote: > > f,g :: Bool -> Int > > f x = 6 > > g x = 6 > > We can in Haskell compute that these two functions are equal, without > solving the halting problem. > > what about these? > f,g :: Bool -> Int > f x = 6 > g x = x `seq` 6 > > As pointed out on #haskell by roconnor, we apparently don't care, this is a > shame... We only care that x == y => f x == g y, and x == y can't tell if > _|_ == _|_. > It's a shame that we can't use this to tell if two functions are equally > lazy (something I would consider part of the semantics of the function). > Bob _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
