Subject: Re: Totaly newbie trying to learn LISP at uni From: Erik Naggum <erik@naggum.no> Date: 10 Oct 2002 22:14:09 +0000 Newsgroups: comp.lang.lisp Message-ID: <3243276849563719@naggum.no> * arien <spammers_suck@getlost.invalid> | So how do you rearrange the code so that you instead do a test for y is | not true? A test whether y is not true is a test whether not-y is true. We use (not y) to produce not-y. When you get more experienced with Common Lisp, you may find that you need a short-hand for this if you do it a lot. If you have a Unicode or even a ISO 8859-1 system, you can write the support code to get ¬y to produce (not y) the same way 'y produces (quote y) in the standard syntax because this is such a frequent thing to want, just like #'foo produces (function foo) which you also need quite frequently in Common Lisp. -- Erik Naggum, Oslo, Norway Act from reason, and failure makes you rethink and study harder. Act from faith, and failure makes you blame someone and push harder.