From ... Path: archiver1.google.com!news1.google.com!sn-xit-02!supernews.com!news-x2.support.nl!deine.net!hamster.europeonline.net!newsfeed.europeonline.net!nslave.kpnqwest.net!nloc.kpnqwest.net!nmaster.kpnqwest.net!nreader2.kpnqwest.net.POSTED!not-for-mail Newsgroups: comp.lang.lisp Subject: Re: setq setf References: <3224632704949565@naggum.net> <3224687455847318@naggum.net> Mail-Copies-To: never From: Erik Naggum Message-ID: <3224703434940626@naggum.net> Organization: Naggum Software, Oslo, Norway Lines: 26 User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.1 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Sat, 09 Mar 2002 22:57:05 GMT X-Complaints-To: newsmaster@KPNQwest.no X-Trace: nreader2.kpnqwest.net 1015714625 193.71.199.50 (Sat, 09 Mar 2002 23:57:05 MET) NNTP-Posting-Date: Sat, 09 Mar 2002 23:57:05 MET Xref: archiver1.google.com comp.lang.lisp:28302 * Kent M Pitman | I think of the difference between SETQ and SETF as being "assignment" vs | "side-effect" and regard it as a linguistic irritation that SETF is | allowed to assign variables, though it obviously has a place (pardon the | pun) in describing places. This distinction seems reasonable, and your explanation about doing something in a lambda is not lost on me, _but_ I conclude that special varriables are therefore different from lexical variables, in that you _can_ pass a symbol to a lambda and have it "side-effect" that binding, or, as it might be implemented, the symbol-value slot, so one should use SETF on special variables. Or do special bindings offer the same kind of "encapsulation" that symbol-macrolet does? | But that's just me. I'm not really advocating anyone think like me. I'm | just noting that there is this other pont of view. I'm presently torn | about how to present this issue in books I'm working on, and am leaning | toward just saying to use SETF in spite of my personal preference. There seems to be an important distinction between lexical and non-lexical data in here, somewhere. /// -- In a fight against something, the fight has value, victory has none. In a fight for something, the fight is a loss, victory merely relief.