X-Received: by 10.66.158.6 with SMTP id wq6mr1312089pab.39.1399389622969; Tue, 06 May 2014 08:20:22 -0700 (PDT) Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!news.glorb.com!r10no1182231igi.0!news-out.google.com!du2ni23815qab.0!nntp.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!news.iecc.com!.POSTED!nerds-end From: George Neuner Newsgroups: comp.compilers Subject: Re: Historical Implementations to Garbage Collectors Date: Tue, 06 May 2014 10:55:03 -0400 Organization: A noiseless patient Spider Lines: 17 Sender: news@iecc.com Approved: comp.compilers@iecc.com Message-ID: <14-05-017@comp.compilers> References: <14-05-001@comp.compilers> <14-05-009@comp.compilers> <14-05-012@comp.compilers> NNTP-Posting-Host: news.iecc.com Mime-Version: 1.0 X-Trace: miucha.iecc.com 1399389622 88665 2001:470:1f07:1126:0:676f:7373:6970 (6 May 2014 15:20:22 GMT) X-Complaints-To: abuse@iecc.com NNTP-Posting-Date: Tue, 6 May 2014 15:20:22 +0000 (UTC) Keywords: code, storage, comment Posted-Date: 06 May 2014 11:20:22 EDT X-submission-address: compilers@iecc.com X-moderator-address: compilers-request@iecc.com X-FAQ-and-archives: http://compilers.iecc.com Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Xref: csiph.com comp.compilers:1242 On Mon, 5 May 2014 00:47:04 +0000 (UTC), Kaz Kylheku wrote: >Why would there be tags; strings don't point to other strings. Though unlikely to be found in an older system due to memory constraints, there are string representations which can share structure: e.g., https://en.wikipedia.org/wiki/Rope_%28data_structure%29 George [You don't need anything that fancy for strings to overlap. With null terminated readonly C-style strings, you can combine "storage" and "rage" and "age". Wih strings represented by a pointer and length, they can overlap anywhere. To garbage collect those I'd think you'd need a per cell bitmap, unless you knew everything was 7-bit ASCII and used the high bit as the flag. -John]