From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f4fd2,23202754c9ce78dd X-Google-Attributes: gidf4fd2,public X-Google-Thread: fac41,15edb893ef79e231 X-Google-Attributes: gidfac41,public X-Google-Thread: 114809,15edb893ef79e231 X-Google-Attributes: gid114809,public X-Google-Thread: 103376,15edb893ef79e231 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2002-01-22 13:59:47 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!logbridge.uoregon.edu!nntp-relay.ihug.net!usenet.net.nz!newsfeeds.ihug.co.nz!ihug.co.nz!newsfeed01.tsnz.net!news02.tsnz.net!bruce From: Bruce Hoult Newsgroups: comp.lang.lisp,comp.lang.ada,comp.lang.eiffel,comp.lang.smalltalk Subject: Re: True faiths ( was Re: The true faith ) References: <%njZ7.279$iR.150960@news3.calgary.shaw.ca> <3c36fbc5_10@news.newsgroups.com> <4idg3u40ermnp682n6igc5gudp7hajkea9@4ax.com> <76be8851.0201101909.9db0718@posting.google.com> <9jtu3u8cq92b05j47uat3412tok6hqu1ki@4ax.com> <3C3F8689.377A9F0F@brising.com> <3219936759616091@naggum.net> <3C483CE7.D61D1BF@removeme.gst.com> <7302e4fa4a.simonwillcocks@RiscPC.enterprise.net> <3C4D9B03.60803@mail.com> User-Agent: MT-NewsWatcher/3.0 (PPC) Message-ID: Date: Wed, 23 Jan 2002 10:59:48 +1300 NNTP-Posting-Host: 203.79.84.103 X-Complaints-To: abuse@tsnz.net X-Trace: news02.tsnz.net 1011736786 203.79.84.103 (Wed, 23 Jan 2002 10:59:46 NZDT) NNTP-Posting-Date: Wed, 23 Jan 2002 10:59:46 NZDT Organization: TelstraSaturn Xref: archiver1.google.com comp.lang.lisp:25008 comp.lang.ada:19197 comp.lang.eiffel:5499 comp.lang.smalltalk:18478 Date: 2002-01-23T10:59:48+13:00 List-Id: In article <3C4D9B03.60803@mail.com>, Hyman Rosen wrote: > Simon Willcocks wrote: > > > I think I'll try to stick to languages with garbage collection. > > > But garbage collection has nothing to do with this problem! > > The problem is handling an assignment when the type contains > bases and subobjects that must be copied, and doing such > copying could cause exceptions. You must arrange for the > copying to succeed, or else leave the destination object in > a consistent state, as well as propogate exceptions back to > the caller. Garbage collection has a *lot* to do with this problem! A large proportion of assignments in languages such as C++ are done merely in order to resolve the question of who owns an object and who is responsible for eventually deleting it. With GC available, objects are seldom copied with pointers to them being passed around instead. You don't care who "owns" the object, because it just magically goes away when all the pointers to it get forgotten. -- Bruce