🚀 go-pugleaf

In article <farrell.712373890@coral.cs.jcu.edu.au>, farrell@coral.cs.jcu.edu.au (John Farrell) writes:
|> In <1992Jul28.140801.21895@crl.dec.com> nikhil@crl.dec.com (R.S. Nikhil) writes:
|> >In article <farrell.712286497@coral.cs.jcu.edu.au>, farrell@coral.cs.jcu.edu.au (John Farrell) writes:
|> >>   *Non-strict* evaluation saves time by not evaluating arguments which are not
|> >> needed.
|> 
|> >Pardon my nit-picking, but this is not true.  I refer you to my earlier posting
|> >(last week?) in which I pointed out that evaluators CAN work on unnecessary
|> >arguments while preserving non-strictness.
|> 
|>   My statement is true if you are implementing non-strict evaluation on a
|> sequential machine, in which case speculative evaluation can cause
|> non-termination unless you can prove that the argument being speculatively
|> evaluated was needed, and at the very least speculatively evaluating an
|> unneeded argument will waste time. Your nit-picking is pardoned :-).
|> 
|> 
|> John

To pick a further nit, you can, of course, simulate parallel evaluation on a
sequential machine, and so preserve non-strictness while working on unnecessary
arguments.

--brian


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