Beginner's question: Memo functions in Haskell

[Jan Kort]

Janis Voigtlaender wrote:
> 
> It would also seem that one needs to write
> 
>  fast = memo slow
> 
> instead, because otherwise a new memo-version of slow might be created
> for every call with some n (subject to let-floating?).
> However, the version:
> 
>   module Fib where
> 
>   import Memo
> 
>   slow 0 = 0
>   slow 1 = 1
>   slow n = fast (n-1) + fast (n-2)
> 
>   fast = memo slow
> 
> is not particularly fast easier. Quite in contrary... strange.
> 
> Janis.
> 

It works under hugs98, but not under ghc5.02.2,
I CC'd the ghc bugs list.

Actually, I was also expecting "fast n = memo slow n"
to work ?

  Jan