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From: lgm@cbnewsc.att.com (lawrence.g.mayka)
Newsgroups: comp.lang.lisp
Subject: Re: Weak Reference in Common Lisp
Message-ID: <1990Aug29.000319.20042@cbnewsc.att.com>
Date: 29 Aug 90 00:03:19 GMT
References: <81084@aerospace.AERO.ORG> <1350026@otter.hpl.hp.com> <3289@skye.ed.ac.uk>
Organization: AT&T Bell Laboratories
Lines: 16

In article <3289@skye.ed.ac.uk> jeff@aiai.UUCP (Jeff Dalton) writes:
>Moreover, I think hash tables in Common Lisp are much less useful than
>they ought to be, because putting something in a hash table prevents
>it from being garbage collected.

Symbolics Genera 8.0 offers a keyword option to MAKE-HASH-TABLE called
:GC-PROTECT-VALUES.  If NIL, table entries are automatically deleted
if a value becomes unreachable other than through the table.  I urge
Common Lisp vendors to standardize on something like this.


	Lawrence G. Mayka
	AT&T Bell Laboratories
	lgm@iexist.att.com

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