On Tue, Jul 28, 2009 at 6:47 AM, Sebastian Fischer<s...@informatik.uni-kiel.de> wrote: >>> perms = sortByM (const [True,False]) > Hence, perm as defined above can yield a list that contains all permutations > of the input (at least once) regardless of the sorting algorithm. > > Where is the hitch?
The algorithm might diverge when given a non-transitive comparison operator. On Spore we had a bug where a NaN got into a list of floats we were sorting and our quicksort corrupted the heap because < isn't transitive on lists with NaNs. -- ryan _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
