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Issue: PROCLAIM-LEXICAL (Version 7)
- To: Moon@STONY-BROOK.SCRC.Symbolics.COM
- Subject: Issue: PROCLAIM-LEXICAL (Version 7)
- From: Jon L White <email@example.com>
- Date: Tue, 27 Sep 88 23:56:21 PDT
- Cc: KMP@STONY-BROOK.SCRC.Symbolics.COM, CL-Cleanup@SAIL.Stanford.EDU, JAR@AI.AI.MIT.EDU
- In-reply-to: David A. Moon's message of Tue, 27 Sep 88 13:37 EDT <19880927173749.1.MOON@EUPHRATES.SCRC.Symbolics.COM>
re: The KMP/EB discussion suggests that the semantics of the proposal are
very confusing even to experts, although perhaps it's just unfamiliar.
I agree. This might be something we shouldn't even think about standard-
izing until some implementor/vendor takes the plunge in a trial balloon,
presumably based on his belief that these semantics are immensely worthwhile
to Common Lisp users -- so important in fact that he's willing to "run ahead"
of the X3J13 committee and use it for a couple of years. Otherwise, without
some practical evidence that there is overwhelming gain to be had, I fear
we could commit ourselves for an enormous implementational headache purely
because it "seemed like a nice idea at the time".
Yes, I remember, I was mildly in favor of the original proposal; but that
was a year and a half ago, and I expected a GLOBAL declaration to mean that
it would be illegal to special-bind that name (hence you could depend on
that name *not* being in the D environment). Had somebody implemented
something like it for their Lisp back then, we might have had results to
talk about now.
Incidentally, Lucid has done a deep-binding implementation -- for QLISP.
Needless to say, it wasn't an overnight project; and the performance
results could be questioned (or else, we could just commit more good
money after bad to keep tweaking it indefinitely). Well, anyway, QLISP
*is* a research project.
I think it would be better to drop the notion of dynamic bindings --
SPECIAL variables -- altogether, than to try to graft a hybrid notion
on top of Common Lisp. There are quite a few folks who really would
like to flush special variables; but that's an issue guaranteed to
cleave the community down the middle.
-- JonL --