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Re: loop macro
Date: 04 Feb 86 16:19:16 EST (Tue)
From: Liz Allen <firstname.lastname@example.org>
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
Your For macro sounds interesting in its own right, but I
get the impression that it is enough different from the
Lisp Machine version that it would not be of much help in
porting Loop-infested Lisp Machine code into Common Lisp.
Is that right? Do you have any experience with such ports?
Well, I've only just started using the Lisp Machine Loop macro
recently and its syntax isn't quite what I tend to expect, so I'm
not sure how much I can say. There was someone who ported YAPS to
a Lisp Machine a while back who said that it was easy to translate
all the for's into loop's so it might not be *too* bad to go the
other way. Probably the biggest thing missing from our for macro
is the ability to accumulate multiple values in a single for (but
then, Franz Lisp 38.91 didn't have the concept of returning multiple
values from a function...). It would probably not be too hard to
add that feature -- the $$val stuff would have to be revised, but
in principle, there is no reason we couldn't extend it (except I'm
trying to work on a PhD thesis!).
I don't understand the general topic of discussion here. This Maryland
FOR macro hasn't a dime's worth of difference from Zetalisp LOOP. The
differences are trifling. I thought the issue with LOOP vs. CL was not
one of trivial differences between a large number of Interlisp-like loop
macros, but rather one of whether we wanted such a thing, extremely
non-lispy, however useful, to some tastes, in the language.