From ... Path: supernews.google.com!sn-xit-02!supernews.com!bignews.mediaways.net!newsfeed.ision.net!ision!news.algonet.se!algonet!neel.uni2.net!uio.no!Norway.EU.net!127.0.0.1!nobody From: Erik Naggum Newsgroups: comp.lang.lisp Subject: Re: Performance tuning Date: 07 Dec 2000 16:16:02 +0000 Organization: Naggum Software; vox: +47 800 35477; gsm: +47 93 256 360; fax: +47 93 270 868; http://naggum.no; http://naggum.net Lines: 30 Message-ID: <3185194562763651@naggum.net> References: <3184953833736032@naggum.net> <3A2C7C38.4F68956A@fisec.com> <3185025504930095@naggum.net> <90jju3$44s$1@reader1.fr.uu.net> <3185044115971786@naggum.net> <3A2E1240.C8911FE@anglia.ac.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: oslo-nntp.eunet.no 976205822 20970 195.0.192.66 (7 Dec 2000 16:17:02 GMT) X-Complaints-To: newsmaster@eunet.no NNTP-Posting-Date: 7 Dec 2000 16:17:02 GMT mail-copies-to: never User-Agent: Gnus/5.0803 (Gnus v5.8.3) Emacs/20.7 Xref: supernews.google.com comp.lang.lisp:4841 * Dr Nick Levine | The language model would have to be changed more than somewhat for the | value of x to be changed. [Effectively, CL always passes numbers and | characters "by value" and everything else "by reference".] That's not really so. That's the catch with bignums. They don't get copied (effectively) when you pass them around, and they cons a _lot_ when they are copied, to there are good reasons to reuse them. I think dpb would be the one operator that it would make sense to let reuse the bignum. Its semantics _is_ to deposit bits into an existing number. | Also, if the zero was destructively modified, how many other zeros | would also change? What would happen to zerop? Ouch! Zero wouldn't magically become a bignum any time soon, would it? | It's also unnerving to think of code whose semantics (as opposed to | efficiency) changes when you pass through the fixnum/bignum boundary. And what semantic changes would that really be? I see fear but little technical argumentation, especially considering the weird non-issue with zero that you bring up. What's really on your mind? #:Erik -- "When you are having a bad day and it seems like everybody is trying to piss you off, remember that it takes 42 muscles to produce a frown, but only 4 muscles to work the trigger of a good sniper rifle." -- Unknown