[plt-scheme] Re: Project Euler was Hash Table implementation

From: David Einstein (deinst at gmail.com)
Date: Mon Aug 6 14:39:33 EDT 2007

Yes and no.  I think an odd streams package would be very useful. (I would
certainly find a use for it.)  However, I think that it should be possible
to get a stream package that neither exhibits the extra forces that the "How
to add laziness to a strict language without being odd" paper addresses, nor
the missing delays that seem to happen with srfi-40.  (No, I have no idea if
it is possible, but I see no reason why it shouldn't be .)

P.S. I am  relieved that many people smarter than me also have problems with
srfi 40.

On 8/6/07, Chongkai Zhu <czhu at cs.utah.edu> wrote:
>
> I have tried SRFI-40. But after a while, I notice it's far too tricky.
> So I go back to my own odd stream implementation. Maybe we need a SRFI
> (or, a package) for odd stream?
>
> Chongkai
>
> David Van Horn wrote:
> >
> > It goes beyond being tricky.  The document and the reference
> > implementation are inconsistent in a fundamental way.  For example,
> > the document states:
> >
> >    "no element of the stream is evaluated until it is accessed."
> >
> > And yet, the following causes an error because the car element is
> > evaluated even though it is never accessed:
> >
> >    (stream-cdr (stream-cons (1) stream-null))
> >
> > David
> >
> > _________________________________________________
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>
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