29 Dec
2008
29 Dec
'08
5:45 p.m.
Yeah, I knew it was fairly unlikely that I was the first to think of this optimization ;-) I just reported the "run-time performance bug" as http://hackage.haskell.org/trac/ghc/ticket/2902 I am using an Intel Core 2 Duo MacBook and GHC 6.10.1, OS X 10.5.6. For the toy example that I submitted, the difference is over a factor of 3x. Thanks, Dave On Dec 29, 2008, at 6:23 AM, Simon Peyton-Jones wrote:
Which version of GHC are you using? GHC 6.10 implements automatically precisely the transformation you give below.
If the difference shows up in GHC 6.10, could you spare a moment to produce a reproducible test case, and record it in GHC's bug tracker?
Thanks
Simon