From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Barry Margolin Newsgroups: gmane.emacs.help Subject: Re: Object identity Date: Tue, 21 Oct 2003 17:19:34 GMT Organization: Level(3) Communications, Woburn, MA Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Message-ID: References: NNTP-Posting-Host: deer.gmane.org X-Trace: sea.gmane.org 1066757491 1306 80.91.224.253 (21 Oct 2003 17:31:31 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Tue, 21 Oct 2003 17:31:31 +0000 (UTC) Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Tue Oct 21 19:31:29 2003 Return-path: Original-Received: from monty-python.gnu.org ([199.232.76.173]) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1AC0Lx-0004TP-00 for ; Tue, 21 Oct 2003 19:31:29 +0200 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.24) id 1AC0Li-0004QB-F4 for geh-help-gnu-emacs@m.gmane.org; Tue, 21 Oct 2003 13:31:14 -0400 Original-Path: shelby.stanford.edu!newsfeed.stanford.edu!bloom-beacon.mit.edu!nycmny1-snh1.gtei.net!crtntx1-snh1.gtei.net!news.gtei.net!news.level3.com.POSTED!53ab2750!not-for-mail Original-Newsgroups: gnu.emacs.help Mail-Copies-To: never X-Newsreader: trn 4.0-test72 (19 April 1999) Originator: barmar@genuity.net (Barry Margolin) Original-Lines: 30 Original-NNTP-Posting-Host: 171.78.176.30 Original-X-Trace: news.level3.com 1066756774 171.78.176.30 (Tue, 21 Oct 2003 17:19:34 GMT) Original-NNTP-Posting-Date: Tue, 21 Oct 2003 17:19:34 GMT Original-Xref: shelby.stanford.edu gnu.emacs.help:117498 Original-To: help-gnu-emacs@gnu.org X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.2 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: main.gmane.org gmane.emacs.help:13429 X-Report-Spam: http://spam.gmane.org/gmane.emacs.help:13429 In article , Stefan Monnier wrote: >>> I still have no clue what it's useful for, so I tend to find such research >>> rather pointless. But I'm probably just missing the point. > >> The OP explained what it's useful for: emulating weak hash tables in a >> system that doesn't have them built in. > >That's not how I understood his article. He seemed to say that he >currently uses an implementation of object-identity which relies >on a weak hash-table but that his Emacs's doesn't implement weakness. >I.e. he seemed to say he needed weak hash-tables to implement >oject-identity, not the other way around. I just reread it and you're correct. >> it's likely that this overhead will be much greater than the memory leak in >> his application. > >If the application is long running a 50% overhead can still be >significantly better than a memory leak. 50% overhead on every object versus leaking something like 1% of objects. I think I'd prefer the latter. -- Barry Margolin, barry.margolin@level3.com Level(3), Woburn, MA *** DON'T SEND TECHNICAL QUESTIONS DIRECTLY TO ME, post them to newsgroups. Please DON'T copy followups to me -- I'll assume it wasn't posted to the group.