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From: bruce@liverpool.ac.uk
Subject: Re: Forcing a symbol to be unbound?
In-Reply-To: birkholz@midnight.com's message of 10 Aug 1995 10:51:12 GMT
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Date: Thu, 10 Aug 1995 13:23:08 GMT
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>>>>> "birkholz" == birkholz  <birkholz@midnight.com> writes:

From> lord@rtl.cygnus.com (Tom Lord)

>     (set! bound-symbol-to-unbind (variable-ref (make-unbound-variable)))

I agree this is bizarre, but Tom Lord did point out that it only
worked because of a bug!

I think the "make-unbound-variable" function has potential meaning,
but perhaps it could use a different name.  I think of variables as
symbols which correspond to cells which may contain values.  I can see
why one might want to make visible (in some weird way) these cells,
without requiring them to be attached immediately to symbols.  I don't
think such things would have any value (or even meaning) in Scheme,
but for low-level mucking about they might be useful.
-- 
Bruce                   Institute of Advanced Scientific Computation
bruce@liverpool.ac.uk   University of Liverpool
http://supr.scm.liv.ac.uk/~bruce/

