And when the need gets big enough you pull out StablePtr and use that. :)
On Sun, Apr 19, 2009 at 10:43 PM, Peter Verswyvelen <bugf...@gmail.com> wrote: > Sometimes I do miss the pragmatic C solution: > - two function pointers that are equal surely represent the same functions > (although in C nothing is really sure ;) > - two function pointers that are different, might or might not represent > that same functions. > But this weak equality can sometimes be handy. > For example, suppose you have a predicate a -> Bool, and a list of these > predicates [a -> Bool], but you want to remove all functions that are > obviously equal in the C way from the list for optimization... Okay big > hack, and one could do this already with reallyUnsafePtrEquality# I guess... > On Sat, Apr 18, 2009 at 6:02 PM, John A. De Goes <j...@n-brain.net> wrote: >> >> Two functions are equal iff they have the same domain and range and the >> same outputs for the same inputs. Simple to state, but extremely difficult >> to implement in a useful way, and impossible to implement in a perfect way. >> >> If you had a compiler or algorithm capable of determining function >> equality, you could use it to prove or disprove arbitrary theorems in >> mathematics. > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe > > _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
