On 14 Apr 2010, at 09:01, Jonas Almström Duregård wrote: >> But if one did start considering bottom to be a value, one would have to >> distinguish different ones. For instance, (error "ABC") vs. (error >> "PQR"). Obviously this is not finite. > > Nor is it computable, since it must distinguish terminating programs > from nonterminating ones (i.e. the halting problem). > > On a side note, since "instance (Finite a, Finite b) => Finite (a -> > b)" should be possible, one can even compare some higher order > functions with this approach ;).
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. Bob_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
