Random questions after a long haskell coding day
Ketil Z. Malde
29 Jan 2002 13:10:54 +0100
"Simon Marlow" <email@example.com> writes:
>> Can we also rely on destructive updates for the monadic arrays?
> In GHC, yes :-)
One more question: I imagine arrays give an opportunity to optimize by
unboxing the contained type -- any chance of that? How much space
would an array of Chars consume compared to a list of Chars?
Meandering back to the original point of O(1) array access - my
feeling is that this should be a specific requirement of the
language. I would like to be able to specify the asymptotic time
comlexity of my programs, but without knowing how primitives behave, I
can't. Usually, I tend to avoid arrays, since I don't know how well
Is there a good reason (i.e. not just allowing lazy implementors use
lists) for *not* specifying it?
> We had a project to run concurrent/parallel Haskell programs on an SMP
> machine, but it is currently stalled. There are some significant
> problems [...]
> The GPH (Glasgow Parallel Haskell) project is the implementation using
> PVM, which runs with a distributed rather than shared heap.
Yes. So it seems PH is the way to go, then. I'll get around to do
some tests, I hope. ATM, it seems I'll use a large globally shared
data structure, this sounds a bit unPVM'ish, but I'll look into it.
> nevertheless, the GPH folks got some good speedups.
(Any GPH folks have any rules of thumb handy?)
> Their implementation is lagging a bit behind the current GHC
> release, however:
I can live with that, I think.
If I haven't seen further, it is by standing in the footprints of giants