Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!asuvax!ncar!midway!tank!stephen From: stephen@estragon.uchicago.edu (Stephen P Spackman) Newsgroups: comp.lang.lisp Subject: Re: Weak Reference in Common Lisp Message-ID: Date: 3 Sep 90 19:06:40 GMT References: <81084@aerospace.AERO.ORG> <1350026@otter.hpl.hp.com> Sender: news@midway.uchicago.edu (News Administrator) Organization: University of Chicago CILS Lines: 16 In-Reply-To: sfk@otter.hpl.hp.com's message of 22 Aug 90 14:42:27 GMT In article <1350026@otter.hpl.hp.com> sfk@otter.hpl.hp.com (Steve Knight) writes: The cost of temporary properties is to make the garbage collection algorithm slightly more complicated & to necessitate rehashing after GC. These are typically small costs. Depending on how you do things, the necessity of rehashing after GC is quite possibly there anyway. And you can always defer rehash until first reference. The biggest cost in *my* implementation was the manhours tracking down the bug where having an object that was the key of an object that was its key made the two objects get their first cells mixed up.... :-) stephen "Well I *had* a correctness proof, I guess I left it in the caf, and it's really a very simple algorithm anyway, what could go wrong?" p spackman stephen@estragon.uchicago.edu 312.702.3982