Am Dienstag 04 August 2009 20:30:58 schrieb Slavomir Kaslev: > On Tue, Aug 4, 2009 at 9:23 PM, Daniel Fischer<[email protected]> > wrote:
> > Which version of ghc are you testing on? I guess, it's more recent than > mine. 6.10.3. But I think if you compiled it with 6.8.*, the library code would still be faster, perhaps by a smaller margin. > > > Apparently the library code is more amenable to the optimiser (note that > > the actual library is faster still: > > > > Prelude Data.List> length $ permutations [1 .. 10] > > 3628800 > > (0.49 secs, 551532812 bytes) > > Prelude Data.List> length $ permutations [1 .. 11] > > 39916800 > > (3.73 secs, 5953485816 bytes) > > > > I have no idea why). > > Probably because it's compiled (and not interpreted) in this case. All my times were from compiled (with -O2) code. The question is, why does the same source code produce slower object code in module Perms than in Data.List? I suppose it's because Data.List was compiled with different command line options, but I've no idea which. _______________________________________________ Glasgow-haskell-users mailing list [email protected] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
