Dear All,
Hal's comments on the use of Evaluation Strategies for controlling
strictness are substantially right, and they are used this way in Eden, a
parallel Haskell. In Glasgow parallel Haskell(GpH) we use them to control
parallel evaluation as well. The key reference is
Algorithm +
On Tue, Aug 20, 2002 at 10:43:39AM +0200, Jan Kybic wrote:
This is what I cannot do for the moment. How do I find out what is
really going on. Any pointers to a relevant
articles/literature? ...
In addition to the other suggestions, see Chapter 6 (Advice on:
sooner, faster, smaller,
Alastair Reid [EMAIL PROTECTED] writes:
http://www.cs.york.ac.uk/fp/profile.html
[York don't seem to put links to their pages on the web. Citeseer
may have some of them.]
Thanks for pointing this out. I've now added lots of links for papers on
that webpage.
Regards,
As you've apparently discovered, the trick is to be lazy but not too
lazy. That is, you want to generate the list lazily but compute a
partial result (i.e., the running total of that part of the list
processed so far) strictly.
Thanks for all reactions. Now my simplified examples
indeed run in
main = print $ sum [0..100]
When you use a sufficiently large number (perhaps 1000 instead
of 100), both ghci and ghc terminate with Stack space
overflow. On the other hand, Hugs (dated December 2001) runs the
example OK and produces the result of 5050.
I have the
On Mon, Aug 19, 2002 at 11:19:41PM +0200, Jan Kybic wrote:
Hello,
I am wrestling with having Haskell (using ghc(i) version 5.02.2)
evaluate things in good order and to garbage collect what he no longer
needs. I could simplify the problem to this simple example:
main = print $ sum
On Mon, Aug 19, 2002 at 11:34:48PM +0100, Alastair Reid wrote:
main = print $ sum [0..100]
...
Hugs uses foldl' instead of foldl to define sum:...
Does it really? That's a violation of the standard: a user's instance
of (+) need not be strict in its left argument. Consider
data Foo
