Daniel Fischer wrote:
Hi,
I have recently come across the curious phenomenon that ghci is sometimes much slower than hugs.
[...]
ms as = zipWith (+) (zipWith (*) as (1:ms as)) (0:1:ms as)
Hugs has(**) a specific optimisation for the case where the left hand side of the declaration occurs as a subexpression in the right hand side.
You can get a similar benefit under ghci if you share the common subexpression by hand:
ms' as = let bs = ms' as in
zipWith (+) (zipWith (*) as (1:bs)) (0:1:bs)(**) I haven't actually seen the code in question, and am repeating something which was on one of the mailing lists a few years ago. So please don't treat this as authoritative!
Regards, Tom
_______________________________________________ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe
